/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You under the Apache License, Version 2.0
    * (the "License"); you may not use this file except in compliance with
    * the License.  You may obtain a copy of the License at
    *
    *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.commons.io;
  
  import java.io.BufferedInputStream;
  import java.io.BufferedOutputStream;
  import java.io.BufferedReader;
  import java.io.BufferedWriter;
  import java.io.ByteArrayInputStream;
  import java.io.CharArrayWriter;
  import java.io.Closeable;
  import java.io.EOFException;
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.OutputStream;
  import java.io.OutputStreamWriter;
  import java.io.PrintWriter;
  import java.io.Reader;
  import java.io.UnsupportedEncodingException;
  import java.io.Writer;
  import java.net.HttpURLConnection;
  import java.net.ServerSocket;
  import java.net.Socket;
  import java.net.URI;
  import java.net.URL;
  import java.net.URLConnection;
  import java.nio.ByteBuffer;
  import java.nio.channels.ReadableByteChannel;
  import java.nio.channels.Selector;
  import java.nio.charset.Charset;
  import java.nio.charset.UnsupportedCharsetException;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  
  import org.apache.commons.io.output.ByteArrayOutputStream;
  import org.apache.commons.io.output.StringBuilderWriter;
  
  /**
   * General IO stream manipulation utilities.
   * <p>
   * This class provides static utility methods for input/output operations.
   * <ul>
   * <li>closeQuietly - these methods close a stream ignoring nulls and exceptions
   * <li>toXxx/read - these methods read data from a stream
   * <li>write - these methods write data to a stream
   * <li>copy - these methods copy all the data from one stream to another
   * <li>contentEquals - these methods compare the content of two streams
   * </ul>
   * <p>
   * The byte-to-char methods and char-to-byte methods involve a conversion step.
   * Two methods are provided in each case, one that uses the platform default
   * encoding and the other which allows you to specify an encoding. You are
   * encouraged to always specify an encoding because relying on the platform
   * default can lead to unexpected results, for example when moving from
   * development to production.
   * <p>
   * All the methods in this class that read a stream are buffered internally.
   * This means that there is no cause to use a <code>BufferedInputStream</code>
   * or <code>BufferedReader</code>. The default buffer size of 4K has been shown
   * to be efficient in tests.
   * <p>
   * Wherever possible, the methods in this class do <em>not</em> flush or close
   * the stream. This is to avoid making non-portable assumptions about the
   * streams' origin and further use. Thus the caller is still responsible for
   * closing streams after use.
   * <p>
   * Origin of code: Excalibur.
   *
   * @version $Id: IOUtils.java 1471767 2013-04-24 23:24:19Z sebb $
   */
  public class IOUtils {
      // NOTE: This class is focussed on InputStream, OutputStream, Reader and
      // Writer. Each method should take at least one of these as a parameter,
      // or return one of them.
  
      private static final int EOF = -1;
      /**
       * The Unix directory separator character.
       */
      public static final char DIR_SEPARATOR_UNIX = '/';
      /**
       * The Windows directory separator character.
      */
     public static final char DIR_SEPARATOR_WINDOWS = '\\';
     /**
      * The system directory separator character.
      */
     public static final char DIR_SEPARATOR = File.separatorChar;
     /**
      * The Unix line separator string.
      */
     public static final String LINE_SEPARATOR_UNIX = "\n";
     /**
      * The Windows line separator string.
      */
     public static final String LINE_SEPARATOR_WINDOWS = "\r\n";
     /**
      * The system line separator string.
      */
     public static final String LINE_SEPARATOR;
 
     static {
         // avoid security issues
         final StringBuilderWriter buf = new StringBuilderWriter(4);
         final PrintWriter out = new PrintWriter(buf);
         out.println();
         LINE_SEPARATOR = buf.toString();
         out.close();
     }
 
     /**
      * The default buffer size ({@value}) to use for
      * {@link #copyLarge(InputStream, OutputStream)}
      * and
      * {@link #copyLarge(Reader, Writer)}
      */
     private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;
 
     /**
      * The default buffer size to use for the skip() methods.
      */
     private static final int SKIP_BUFFER_SIZE = 2048;
 
     // Allocated in the relevant skip method if necessary.
     /*
      * N.B. no need to synchronize these because:
      * - we don't care if the buffer is created multiple times (the data is ignored)
      * - we always use the same size buffer, so if it it is recreated it will still be OK
      * (if the buffer size were variable, we would need to synch. to ensure some other thread
      * did not create a smaller one)
      */
     private static char[] SKIP_CHAR_BUFFER;
     private static byte[] SKIP_BYTE_BUFFER;
 
     /**
      * Instances should NOT be constructed in standard programming.
      */
     public IOUtils() {
         super();
     }
 
     //-----------------------------------------------------------------------
 
     /**
      * Closes a URLConnection.
      *
      * @param conn the connection to close.
      * @since 2.4
      */
     public static void close(final URLConnection conn) {
         if (conn instanceof HttpURLConnection) {
             ((HttpURLConnection) conn).disconnect();
         }
     }
 
     /**
      * Closes an <code>Reader</code> unconditionally.
      * <p>
      * Equivalent to {@link Reader#close()}, except any exceptions will be ignored.
      * This is typically used in finally blocks.
      * <p>
      * Example code:
      * <pre>
      *   char[] data = new char[1024];
      *   Reader in = null;
      *   try {
      *       in = new FileReader("foo.txt");
      *       in.read(data);
      *       in.close(); //close errors are handled
      *   } catch (Exception e) {
      *       // error handling
      *   } finally {
      *       IOUtils.closeQuietly(in);
      *   }
      * </pre>
      *
      * @param input  the Reader to close, may be null or already closed
      */
     public static void closeQuietly(final Reader input) {
         closeQuietly((Closeable)input);
     }
 
     /**
      * Closes an <code>Writer</code> unconditionally.
      * <p>
      * Equivalent to {@link Writer#close()}, except any exceptions will be ignored.
      * This is typically used in finally blocks.
      * <p>
      * Example code:
      * <pre>
      *   Writer out = null;
      *   try {
      *       out = new StringWriter();
      *       out.write("Hello World");
      *       out.close(); //close errors are handled
      *   } catch (Exception e) {
      *       // error handling
      *   } finally {
      *       IOUtils.closeQuietly(out);
      *   }
      * </pre>
      *
      * @param output  the Writer to close, may be null or already closed
      */
     public static void closeQuietly(final Writer output) {
         closeQuietly((Closeable)output);
     }
 
     /**
      * Closes an <code>InputStream</code> unconditionally.
      * <p>
      * Equivalent to {@link InputStream#close()}, except any exceptions will be ignored.
      * This is typically used in finally blocks.
      * <p>
      * Example code:
      * <pre>
      *   byte[] data = new byte[1024];
      *   InputStream in = null;
      *   try {
      *       in = new FileInputStream("foo.txt");
      *       in.read(data);
      *       in.close(); //close errors are handled
      *   } catch (Exception e) {
      *       // error handling
      *   } finally {
      *       IOUtils.closeQuietly(in);
      *   }
      * </pre>
      *
      * @param input  the InputStream to close, may be null or already closed
      */
     public static void closeQuietly(final InputStream input) {
         closeQuietly((Closeable)input);
     }
 
     /**
      * Closes an <code>OutputStream</code> unconditionally.
      * <p>
      * Equivalent to {@link OutputStream#close()}, except any exceptions will be ignored.
      * This is typically used in finally blocks.
      * <p>
      * Example code:
      * <pre>
      * byte[] data = "Hello, World".getBytes();
      *
      * OutputStream out = null;
      * try {
      *     out = new FileOutputStream("foo.txt");
      *     out.write(data);
      *     out.close(); //close errors are handled
      * } catch (IOException e) {
      *     // error handling
      * } finally {
      *     IOUtils.closeQuietly(out);
      * }
      * </pre>
      *
      * @param output  the OutputStream to close, may be null or already closed
      */
     public static void closeQuietly(final OutputStream output) {
         closeQuietly((Closeable)output);
     }
 
     /**
      * Closes a <code>Closeable</code> unconditionally.
      * <p>
      * Equivalent to {@link Closeable#close()}, except any exceptions will be ignored.
      * This is typically used in finally blocks.
      * <p>
      * Example code:
      * <pre>
      *   Closeable closeable = null;
      *   try {
      *       closeable = new FileReader("foo.txt");
      *       // process closeable
      *       closeable.close();
      *   } catch (Exception e) {
      *       // error handling
      *   } finally {
      *       IOUtils.closeQuietly(closeable);
      *   }
      * </pre>
      *
      * @param closeable the object to close, may be null or already closed
      * @since 2.0
      */
     public static void closeQuietly(final Closeable closeable) {
         try {
             if (closeable != null) {
                 closeable.close();
             }
         } catch (final IOException ioe) {
             // ignore
         }
     }
 
     /**
      * Closes a <code>Socket</code> unconditionally.
      * <p>
      * Equivalent to {@link Socket#close()}, except any exceptions will be ignored.
      * This is typically used in finally blocks.
      * <p>
      * Example code:
      * <pre>
      *   Socket socket = null;
      *   try {
      *       socket = new Socket("http://www.foo.com/", 80);
      *       // process socket
      *       socket.close();
      *   } catch (Exception e) {
      *       // error handling
      *   } finally {
      *       IOUtils.closeQuietly(socket);
      *   }
      * </pre>
      *
      * @param sock the Socket to close, may be null or already closed
      * @since 2.0
      */
     public static void closeQuietly(final Socket sock){
         if (sock != null){
             try {
                 sock.close();
             } catch (final IOException ioe) {
                 // ignored
             }
         }
     }
 
     /**
      * Closes a <code>Selector</code> unconditionally.
      * <p>
      * Equivalent to {@link Selector#close()}, except any exceptions will be ignored.
      * This is typically used in finally blocks.
      * <p>
      * Example code:
      * <pre>
      *   Selector selector = null;
      *   try {
      *       selector = Selector.open();
      *       // process socket
      *
      *   } catch (Exception e) {
      *       // error handling
      *   } finally {
      *       IOUtils.closeQuietly(selector);
      *   }
      * </pre>
      *
      * @param selector the Selector to close, may be null or already closed
      * @since 2.2
      */
     public static void closeQuietly(final Selector selector){
         if (selector != null){
             try {
               selector.close();
             } catch (final IOException ioe) {
                 // ignored
             }
         }
     }
 
     /**
      * Closes a <code>ServerSocket</code> unconditionally.
      * <p>
      * Equivalent to {@link ServerSocket#close()}, except any exceptions will be ignored.
      * This is typically used in finally blocks.
      * <p>
      * Example code:
      * <pre>
      *   ServerSocket socket = null;
      *   try {
      *       socket = new ServerSocket();
      *       // process socket
      *       socket.close();
      *   } catch (Exception e) {
      *       // error handling
      *   } finally {
      *       IOUtils.closeQuietly(socket);
      *   }
      * </pre>
      *
      * @param sock the ServerSocket to close, may be null or already closed
      * @since 2.2
      */
     public static void closeQuietly(final ServerSocket sock){
         if (sock != null){
             try {
                 sock.close();
             } catch (final IOException ioe) {
                 // ignored
             }
         }
     }
 
     /**
      * Fetches entire contents of an <code>InputStream</code> and represent
      * same data as result InputStream.
      * <p>
      * This method is useful where,
      * <ul>
      * <li>Source InputStream is slow.</li>
      * <li>It has network resources associated, so we cannot keep it open for
      * long time.</li>
      * <li>It has network timeout associated.</li>
      * </ul>
      * It can be used in favor of {@link #toByteArray(InputStream)}, since it
      * avoids unnecessary allocation and copy of byte[].<br>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param input Stream to be fully buffered.
      * @return A fully buffered stream.
      * @throws IOException if an I/O error occurs
      * @since 2.0
      */
     public static InputStream toBufferedInputStream(final InputStream input) throws IOException {
         return ByteArrayOutputStream.toBufferedInputStream(input);
     }
 
     /**
      * Returns the given reader if it is a {@link BufferedReader}, otherwise creates a BufferedReader from the given
      * reader.
      *
      * @param reader
      *            the reader to wrap or return (not null)
      * @return the given reader or a new {@link BufferedReader} for the given reader
      * @since 2.2
      * @see #asBufferedReader(Reader)
      * @throws NullPointerException if the input parameter is null
      */
     public static BufferedReader toBufferedReader(final Reader reader) {
         return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader);
     }
 
     /**
      * Returns the given reader if it is already a {@link BufferedReader}, otherwise creates a BufferedReader from the given
      * reader.
      *
      * @param reader
      *            the reader to wrap or return (not null)
      * @return the given reader or a new {@link BufferedReader} for the given reader
      * @since 2.5
      * @throws NullPointerException if the input parameter is null
      */
     public static BufferedReader asBufferedReader(final Reader reader) {
         return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader);
     }
 
     /**
      * Returns the given Writer if it is already a {@link BufferedWriter}, otherwise creates a BufferedWriter from the given
      * Writer.
      *
      * @param writer
      *            the Writer to wrap or return (not null)
      * @return the given Writer or a new {@link BufferedWriter} for the given Writer
      * @since 2.5
      * @throws NullPointerException if the input parameter is null
      */
     public static BufferedWriter asBufferedWriter(final Writer writer) {
         return writer instanceof BufferedWriter ? (BufferedWriter) writer : new BufferedWriter(writer);
     }
 
     /**
      * Returns the given OutputStream if it is already a {@link BufferedOutputStream}, otherwise creates a BufferedOutputStream from the given
      * OutputStream.
      *
      * @param outputStream
      *            the OutputStream to wrap or return (not null)
      * @return the given OutputStream or a new {@link BufferedOutputStream} for the given OutputStream
      * @since 2.5
      * @throws NullPointerException if the input parameter is null
      */
     public static BufferedOutputStream asBufferedOutputStream(final OutputStream outputStream) {
         // reject null early on rather than waiting for IO operation to fail
         if (outputStream == null) { // not checked by BufferedOutputStream
             throw new NullPointerException();
         }
         return outputStream instanceof BufferedOutputStream ? (BufferedOutputStream) outputStream : new BufferedOutputStream(outputStream);
     }
 
     /**
      * Returns the given InputStream if it is already a {@link BufferedInputStream}, otherwise creates a BufferedInputStream from the given
      * InputStream.
      *
      * @param inputStream
      *            the InputStream to wrap or return (not null)
      * @return the given InputStream or a new {@link BufferedInputStream} for the given InputStream
      * @since 2.5
      * @throws NullPointerException if the input parameter is null
      */
     public static BufferedInputStream asBufferedInputStream(final InputStream inputStream) {
         // reject null early on rather than waiting for IO operation to fail
         if (inputStream == null) { // not checked by BufferedInputStream
             throw new NullPointerException();
         }
         return inputStream instanceof BufferedInputStream ? (BufferedInputStream) inputStream : new BufferedInputStream(inputStream);
     }
 
     // read toByteArray
     //-----------------------------------------------------------------------
     /**
      * Gets the contents of an <code>InputStream</code> as a <code>byte[]</code>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param input  the <code>InputStream</code> to read from
      * @return the requested byte array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      */
     public static byte[] toByteArray(final InputStream input) throws IOException {
         final ByteArrayOutputStream output = new ByteArrayOutputStream();
         copy(input, output);
         return output.toByteArray();
     }
 
     /**
      * Gets contents of an <code>InputStream</code> as a <code>byte[]</code>.
      * Use this method instead of <code>toByteArray(InputStream)</code>
      * when <code>InputStream</code> size is known.
      * <b>NOTE:</b> the method checks that the length can safely be cast to an int without truncation
      * before using {@link IOUtils#toByteArray(java.io.InputStream, int)} to read into the byte array.
      * (Arrays can have no more than Integer.MAX_VALUE entries anyway)
      *
      * @param input the <code>InputStream</code> to read from
      * @param size the size of <code>InputStream</code>
      * @return the requested byte array
      * @throws IOException if an I/O error occurs or <code>InputStream</code> size differ from parameter size
      * @throws IllegalArgumentException if size is less than zero or size is greater than Integer.MAX_VALUE
      * @see IOUtils#toByteArray(java.io.InputStream, int)
      * @since 2.1
      */
     public static byte[] toByteArray(final InputStream input, final long size) throws IOException {
 
       if(size > Integer.MAX_VALUE) {
           throw new IllegalArgumentException("Size cannot be greater than Integer max value: " + size);
       }
 
       return toByteArray(input, (int) size);
     }
 
     /**
      * Gets the contents of an <code>InputStream</code> as a <code>byte[]</code>.
      * Use this method instead of <code>toByteArray(InputStream)</code>
      * when <code>InputStream</code> size is known
      * @param input the <code>InputStream</code> to read from
      * @param size the size of <code>InputStream</code>
      * @return the requested byte array
      * @throws IOException if an I/O error occurs or <code>InputStream</code> size differ from parameter size
      * @throws IllegalArgumentException if size is less than zero
      * @since 2.1
      */
     public static byte[] toByteArray(final InputStream input, final int size) throws IOException {
 
         if (size < 0) {
             throw new IllegalArgumentException("Size must be equal or greater than zero: " + size);
         }
 
         if (size == 0) {
             return new byte[0];
         }
 
         final byte[] data = new byte[size];
         int offset = 0;
         int readed;
 
         while (offset < size && (readed = input.read(data, offset, size - offset)) != EOF) {
             offset += readed;
         }
 
         if (offset != size) {
             throw new IOException("Unexpected readed size. current: " + offset + ", excepted: " + size);
         }
 
         return data;
     }
 
     /**
      * Gets the contents of a <code>Reader</code> as a <code>byte[]</code>
      * using the default character encoding of the platform.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      *
      * @param input  the <code>Reader</code> to read from
      * @return the requested byte array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @deprecated 2.5 use {@link #toByteArray(Reader, Charset)} instead
      */
     @Deprecated
     public static byte[] toByteArray(final Reader input) throws IOException {
         return toByteArray(input, Charset.defaultCharset());
     }
 
     /**
      * Gets the contents of a <code>Reader</code> as a <code>byte[]</code>
      * using the specified character encoding.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      *
      * @param input  the <code>Reader</code> to read from
      * @param encoding  the encoding to use, null means platform default
      * @return the requested byte array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static byte[] toByteArray(final Reader input, final Charset encoding) throws IOException {
         final ByteArrayOutputStream output = new ByteArrayOutputStream();
         copy(input, output, encoding);
         return output.toByteArray();
     }
 
     /**
      * Gets the contents of a <code>Reader</code> as a <code>byte[]</code>
      * using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      *
      * @param input  the <code>Reader</code> to read from
      * @param encoding  the encoding to use, null means platform default
      * @return the requested byte array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static byte[] toByteArray(final Reader input, final String encoding) throws IOException {
         return toByteArray(input, Charsets.toCharset(encoding));
     }
 
     /**
      * Gets the contents of a <code>String</code> as a <code>byte[]</code>
      * using the default character encoding of the platform.
      * <p>
      * This is the same as {@link String#getBytes()}.
      *
      * @param input  the <code>String</code> to convert
      * @return the requested byte array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs (never occurs)
      * @deprecated 2.5 Use {@link String#getBytes()} instead
      */
     @Deprecated
     public static byte[] toByteArray(final String input) throws IOException {
         // make explicit the use of the default charset
         return input.getBytes(Charset.defaultCharset());
     }
 
     /**
      * Gets the contents of a <code>URI</code> as a <code>byte[]</code>.
      *
      * @param uri
      *            the <code>URI</code> to read
      * @return the requested byte array
      * @throws NullPointerException
      *             if the uri is null
      * @throws IOException
      *             if an I/O exception occurs
      * @since 2.4
      */
     public static byte[] toByteArray(final URI uri) throws IOException {
         return IOUtils.toByteArray(uri.toURL());
     }
 
     /**
      * Gets the contents of a <code>URL</code> as a <code>byte[]</code>.
      *
      * @param url
      *            the <code>URL</code> to read
      * @return the requested byte array
      * @throws NullPointerException
      *             if the input is null
      * @throws IOException
      *             if an I/O exception occurs
      * @since 2.4
      */
     public static byte[] toByteArray(final URL url) throws IOException {
         final URLConnection conn = url.openConnection();
         try {
             return IOUtils.toByteArray(conn);
         } finally {
             close(conn);
         }
     }
 
     /**
      * Gets the contents of a <code>URLConnection</code> as a <code>byte[]</code>.
      *
      * @param urlConn
      *            the <code>URLConnection</code> to read
      * @return the requested byte array
      * @throws NullPointerException
      *             if the urlConn is null
      * @throws IOException
      *             if an I/O exception occurs
      * @since 2.4
      */
     public static byte[] toByteArray(final URLConnection urlConn) throws IOException {
         final InputStream inputStream = urlConn.getInputStream();
         try {
             return IOUtils.toByteArray(inputStream);
         } finally {
             inputStream.close();
         }
     }
 
     // read char[]
     //-----------------------------------------------------------------------
     /**
      * Gets the contents of an <code>InputStream</code> as a character array
      * using the default character encoding of the platform.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param is  the <code>InputStream</code> to read from
      * @return the requested character array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #toCharArray(InputStream, Charset)} instead
      */
     @Deprecated
     public static char[] toCharArray(final InputStream is) throws IOException {
         return toCharArray(is, Charset.defaultCharset());
     }
 
     /**
      * Gets the contents of an <code>InputStream</code> as a character array
      * using the specified character encoding.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param is  the <code>InputStream</code> to read from
      * @param encoding  the encoding to use, null means platform default
      * @return the requested character array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static char[] toCharArray(final InputStream is, final Charset encoding)
             throws IOException {
         final CharArrayWriter output = new CharArrayWriter();
         copy(is, output, encoding);
         return output.toCharArray();
     }
 
     /**
      * Gets the contents of an <code>InputStream</code> as a character array
      * using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param is  the <code>InputStream</code> to read from
      * @param encoding  the encoding to use, null means platform default
      * @return the requested character array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static char[] toCharArray(final InputStream is, final String encoding) throws IOException {
         return toCharArray(is, Charsets.toCharset(encoding));
     }
 
     /**
      * Gets the contents of a <code>Reader</code> as a character array.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      *
      * @param input  the <code>Reader</code> to read from
      * @return the requested character array
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static char[] toCharArray(final Reader input) throws IOException {
         final CharArrayWriter sw = new CharArrayWriter();
         copy(input, sw);
         return sw.toCharArray();
     }
 
     // read toString
     //-----------------------------------------------------------------------
     /**
      * Gets the contents of an <code>InputStream</code> as a String
      * using the default character encoding of the platform.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param input  the <code>InputStream</code> to read from
      * @return the requested String
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @deprecated 2.5 use {@link #toString(InputStream, Charset)} instead
      */
     @Deprecated
     public static String toString(final InputStream input) throws IOException {
         return toString(input, Charset.defaultCharset());
     }
 
     /**
      * Gets the contents of an <code>InputStream</code> as a String
      * using the specified character encoding.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * </p>
      * @param input  the <code>InputStream</code> to read from
      * @param encoding  the encoding to use, null means platform default
      * @return the requested String
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static String toString(final InputStream input, final Charset encoding) throws IOException {
         final StringBuilderWriter sw = new StringBuilderWriter();
         copy(input, sw, encoding);
         return sw.toString();
     }
 
     /**
      * Gets the contents of an <code>InputStream</code> as a String
      * using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param input  the <code>InputStream</code> to read from
      * @param encoding  the encoding to use, null means platform default
      * @return the requested String
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      */
     public static String toString(final InputStream input, final String encoding)
             throws IOException {
         return toString(input, Charsets.toCharset(encoding));
     }
 
     /**
      * Gets the contents of a <code>Reader</code> as a String.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      *
      * @param input  the <code>Reader</code> to read from
      * @return the requested String
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      */
     public static String toString(final Reader input) throws IOException {
         final StringBuilderWriter sw = new StringBuilderWriter();
         copy(input, sw);
         return sw.toString();
     }
 
     /**
      * Gets the contents at the given URI.
      *
      * @param uri
      *            The URI source.
      * @return The contents of the URL as a String.
      * @throws IOException if an I/O exception occurs.
      * @since 2.1
      * @deprecated 2.5 use {@link #toString(URI, Charset)} instead
      */
     @Deprecated
     public static String toString(final URI uri) throws IOException {
         return toString(uri, Charset.defaultCharset());
     }
 
     /**
      * Gets the contents at the given URI.
      *
      * @param uri
      *            The URI source.
      * @param encoding
      *            The encoding name for the URL contents.
      * @return The contents of the URL as a String.
      * @throws IOException if an I/O exception occurs.
      * @since 2.3.
      */
     public static String toString(final URI uri, final Charset encoding) throws IOException {
         return toString(uri.toURL(), Charsets.toCharset(encoding));
     }
 
     /**
      * Gets the contents at the given URI.
      *
      * @param uri
      *            The URI source.
      * @param encoding
      *            The encoding name for the URL contents.
      * @return The contents of the URL as a String.
      * @throws IOException if an I/O exception occurs.
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 2.1
      */
     public static String toString(final URI uri, final String encoding) throws IOException {
         return toString(uri, Charsets.toCharset(encoding));
     }
 
     /**
      * Gets the contents at the given URL.
      *
      * @param url
      *            The URL source.
      * @return The contents of the URL as a String.
      * @throws IOException if an I/O exception occurs.
      * @since 2.1
      * @deprecated 2.5 use {@link #toString(URL, Charset)} instead
      */
     @Deprecated
     public static String toString(final URL url) throws IOException {
         return toString(url, Charset.defaultCharset());
     }
 
     /**
      * Gets the contents at the given URL.
      *
      * @param url
      *            The URL source.
      * @param encoding
      *            The encoding name for the URL contents.
      * @return The contents of the URL as a String.
      * @throws IOException if an I/O exception occurs.
      * @since 2.3
      */
     public static String toString(final URL url, final Charset encoding) throws IOException {
         final InputStream inputStream = url.openStream();
         try {
             return toString(inputStream, encoding);
         } finally {
             inputStream.close();
         }
     }
 
     /**
      * Gets the contents at the given URL.
      *
      * @param url
      *            The URL source.
      * @param encoding
      *            The encoding name for the URL contents.
      * @return The contents of the URL as a String.
      * @throws IOException if an I/O exception occurs.
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 2.1
      */
     public static String toString(final URL url, final String encoding) throws IOException {
         return toString(url, Charsets.toCharset(encoding));
     }
 
     /**
      * Gets the contents of a <code>byte[]</code> as a String
      * using the default character encoding of the platform.
      *
      * @param input the byte array to read from
      * @return the requested String
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs (never occurs)
      * @deprecated 2.5 Use {@link String#String(byte[])} instead
      */
     @Deprecated
     public static String toString(final byte[] input) throws IOException {
         // make explicit the use of the default charset
         return new String(input, Charset.defaultCharset());
     }
 
     /**
      * Gets the contents of a <code>byte[]</code> as a String
      * using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      *
      * @param input the byte array to read from
      * @param encoding  the encoding to use, null means platform default
      * @return the requested String
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs (never occurs)
      */
     public static String toString(final byte[] input, final String encoding) throws IOException {
         return new String(input, Charsets.toCharset(encoding));
     }
 
     // readLines
     //-----------------------------------------------------------------------
     /**
      * Gets the contents of an <code>InputStream</code> as a list of Strings,
      * one entry per line, using the default character encoding of the platform.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param input  the <code>InputStream</code> to read from, not null
      * @return the list of Strings, never null
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #readLines(InputStream, Charset)} instead
      */
     @Deprecated
     public static List<String> readLines(final InputStream input) throws IOException {
         return readLines(input, Charset.defaultCharset());
     }
 
     /**
      * Gets the contents of an <code>InputStream</code> as a list of Strings,
      * one entry per line, using the specified character encoding.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param input  the <code>InputStream</code> to read from, not null
      * @param encoding  the encoding to use, null means platform default
      * @return the list of Strings, never null
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static List<String> readLines(final InputStream input, final Charset encoding) throws IOException {
         final InputStreamReader reader = new InputStreamReader(input, Charsets.toCharset(encoding));
         return readLines(reader);
     }
 
     /**
      * Gets the contents of an <code>InputStream</code> as a list of Strings,
      * one entry per line, using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      *
      * @param input  the <code>InputStream</code> to read from, not null
      * @param encoding  the encoding to use, null means platform default
      * @return the list of Strings, never null
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static List<String> readLines(final InputStream input, final String encoding) throws IOException {
         return readLines(input, Charsets.toCharset(encoding));
     }
 
     /**
      * Gets the contents of a <code>Reader</code> as a list of Strings,
      * one entry per line.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      *
      * @param input  the <code>Reader</code> to read from, not null
      * @return the list of Strings, never null
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static List<String> readLines(final Reader input) throws IOException {
         final BufferedReader reader = toBufferedReader(input);
         final List<String> list = new ArrayList<String>();
         String line = reader.readLine();
         while (line != null) {
             list.add(line);
             line = reader.readLine();
         }
         return list;
     }
 
     // lineIterator
     //-----------------------------------------------------------------------
     /**
      * Returns an Iterator for the lines in a <code>Reader</code>.
      * <p>
      * <code>LineIterator</code> holds a reference to the open
      * <code>Reader</code> specified here. When you have finished with the
      * iterator you should close the reader to free internal resources.
      * This can be done by closing the reader directly, or by calling
      * {@link LineIterator#close()} or {@link LineIterator#closeQuietly(LineIterator)}.
      * <p>
      * The recommended usage pattern is:
      * <pre>
      * try {
      *   LineIterator it = IOUtils.lineIterator(reader);
      *   while (it.hasNext()) {
      *     String line = it.nextLine();
      *     /// do something with line
      *   }
      * } finally {
      *   IOUtils.closeQuietly(reader);
      * }
      * </pre>
      *
      * @param reader  the <code>Reader</code> to read from, not null
      * @return an Iterator of the lines in the reader, never null
      * @throws IllegalArgumentException if the reader is null
      * @since 1.2
      */
     public static LineIterator lineIterator(final Reader reader) {
         return new LineIterator(reader);
     }
 
     /**
      * Returns an Iterator for the lines in an <code>InputStream</code>, using
      * the character encoding specified (or default encoding if null).
      * <p>
      * <code>LineIterator</code> holds a reference to the open
      * <code>InputStream</code> specified here. When you have finished with
      * the iterator you should close the stream to free internal resources.
      * This can be done by closing the stream directly, or by calling
      * {@link LineIterator#close()} or {@link LineIterator#closeQuietly(LineIterator)}.
      * <p>
      * The recommended usage pattern is:
      * <pre>
      * try {
      *   LineIterator it = IOUtils.lineIterator(stream, charset);
      *   while (it.hasNext()) {
      *     String line = it.nextLine();
      *     /// do something with line
      *   }
      * } finally {
      *   IOUtils.closeQuietly(stream);
      * }
      * </pre>
      *
      * @param input  the <code>InputStream</code> to read from, not null
      * @param encoding  the encoding to use, null means platform default
      * @return an Iterator of the lines in the reader, never null
      * @throws IllegalArgumentException if the input is null
      * @throws IOException if an I/O error occurs, such as if the encoding is invalid
      * @since 2.3
      */
     public static LineIterator lineIterator(final InputStream input, final Charset encoding) throws IOException {
         return new LineIterator(new InputStreamReader(input, Charsets.toCharset(encoding)));
     }
 
     /**
      * Returns an Iterator for the lines in an <code>InputStream</code>, using
      * the character encoding specified (or default encoding if null).
      * <p>
      * <code>LineIterator</code> holds a reference to the open
      * <code>InputStream</code> specified here. When you have finished with
      * the iterator you should close the stream to free internal resources.
      * This can be done by closing the stream directly, or by calling
      * {@link LineIterator#close()} or {@link LineIterator#closeQuietly(LineIterator)}.
      * <p>
      * The recommended usage pattern is:
      * <pre>
      * try {
      *   LineIterator it = IOUtils.lineIterator(stream, "UTF-8");
      *   while (it.hasNext()) {
      *     String line = it.nextLine();
      *     /// do something with line
      *   }
      * } finally {
      *   IOUtils.closeQuietly(stream);
      * }
      * </pre>
      *
      * @param input  the <code>InputStream</code> to read from, not null
      * @param encoding  the encoding to use, null means platform default
      * @return an Iterator of the lines in the reader, never null
      * @throws IllegalArgumentException if the input is null
      * @throws IOException if an I/O error occurs, such as if the encoding is invalid
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.2
      */
     public static LineIterator lineIterator(final InputStream input, final String encoding) throws IOException {
         return lineIterator(input, Charsets.toCharset(encoding));
     }
 
     //-----------------------------------------------------------------------
     /**
      * Converts the specified CharSequence to an input stream, encoded as bytes
      * using the default character encoding of the platform.
      *
      * @param input the CharSequence to convert
      * @return an input stream
      * @since 2.0
      * @deprecated 2.5 use {@link #toInputStream(CharSequence, Charset)} instead
      */
     @Deprecated
     public static InputStream toInputStream(final CharSequence input) {
         return toInputStream(input, Charset.defaultCharset());
     }
 
     /**
      * Converts the specified CharSequence to an input stream, encoded as bytes
      * using the specified character encoding.
      *
      * @param input the CharSequence to convert
      * @param encoding the encoding to use, null means platform default
      * @return an input stream
      * @since 2.3
      */
     public static InputStream toInputStream(final CharSequence input, final Charset encoding) {
         return toInputStream(input.toString(), encoding);
     }
 
     /**
      * Converts the specified CharSequence to an input stream, encoded as bytes
      * using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      *
      * @param input the CharSequence to convert
      * @param encoding the encoding to use, null means platform default
      * @return an input stream
      * @throws IOException if the encoding is invalid
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 2.0
      */
     public static InputStream toInputStream(final CharSequence input, final String encoding) throws IOException {
         return toInputStream(input, Charsets.toCharset(encoding));
     }
 
     //-----------------------------------------------------------------------
     /**
      * Converts the specified string to an input stream, encoded as bytes
      * using the default character encoding of the platform.
      *
      * @param input the string to convert
      * @return an input stream
      * @since 1.1
      * @deprecated 2.5 use {@link #toInputStream(String, Charset)} instead
      */
     @Deprecated
     public static InputStream toInputStream(final String input) {
         return toInputStream(input, Charset.defaultCharset());
     }
 
     /**
      * Converts the specified string to an input stream, encoded as bytes
      * using the specified character encoding.
      *
      * @param input the string to convert
      * @param encoding the encoding to use, null means platform default
      * @return an input stream
      * @since 2.3
      */
     public static InputStream toInputStream(final String input, final Charset encoding) {
         return new ByteArrayInputStream(input.getBytes(Charsets.toCharset(encoding)));
     }
 
     /**
      * Converts the specified string to an input stream, encoded as bytes
      * using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      *
      * @param input the string to convert
      * @param encoding the encoding to use, null means platform default
      * @return an input stream
      * @throws IOException if the encoding is invalid
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static InputStream toInputStream(final String input, final String encoding) throws IOException {
         final byte[] bytes = input.getBytes(Charsets.toCharset(encoding));
         return new ByteArrayInputStream(bytes);
     }
 
     // write byte[]
     //-----------------------------------------------------------------------
     /**
      * Writes bytes from a <code>byte[]</code> to an <code>OutputStream</code>.
      *
      * @param data  the byte array to write, do not modify during output,
      * null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static void write(final byte[] data, final OutputStream output)
             throws IOException {
         if (data != null) {
             output.write(data);
         }
     }
 
     /**
      * Writes bytes from a <code>byte[]</code> to chars on a <code>Writer</code>
      * using the default character encoding of the platform.
      * <p>
      * This method uses {@link String#String(byte[])}.
      *
      * @param data  the byte array to write, do not modify during output,
      * null ignored
      * @param output  the <code>Writer</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #write(byte[], Writer, Charset)} instead
      */
     @Deprecated
     public static void write(final byte[] data, final Writer output) throws IOException {
         write(data, output, Charset.defaultCharset());
     }
 
     /**
      * Writes bytes from a <code>byte[]</code> to chars on a <code>Writer</code>
      * using the specified character encoding.
      * <p>
      * This method uses {@link String#String(byte[], String)}.
      *
      * @param data  the byte array to write, do not modify during output,
      * null ignored
      * @param output  the <code>Writer</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static void write(final byte[] data, final Writer output, final Charset encoding) throws IOException {
         if (data != null) {
             output.write(new String(data, Charsets.toCharset(encoding)));
         }
     }
 
     /**
      * Writes bytes from a <code>byte[]</code> to chars on a <code>Writer</code>
      * using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method uses {@link String#String(byte[], String)}.
      *
      * @param data  the byte array to write, do not modify during output,
      * null ignored
      * @param output  the <code>Writer</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static void write(final byte[] data, final Writer output, final String encoding) throws IOException {
         write(data, output, Charsets.toCharset(encoding));
     }
 
     // write char[]
     //-----------------------------------------------------------------------
     /**
      * Writes chars from a <code>char[]</code> to a <code>Writer</code>
      * using the default character encoding of the platform.
      *
      * @param data  the char array to write, do not modify during output,
      * null ignored
      * @param output  the <code>Writer</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static void write(final char[] data, final Writer output) throws IOException {
         if (data != null) {
             output.write(data);
         }
     }
 
     /**
      * Writes chars from a <code>char[]</code> to bytes on an
      * <code>OutputStream</code>.
      * <p>
      * This method uses {@link String#String(char[])} and
      * {@link String#getBytes()}.
      *
      * @param data  the char array to write, do not modify during output,
      * null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #write(char[], OutputStream, Charset)} instead
      */
     @Deprecated
     public static void write(final char[] data, final OutputStream output)
             throws IOException {
         write(data, output, Charset.defaultCharset());
     }
 
     /**
      * Writes chars from a <code>char[]</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding.
      * <p>
      * This method uses {@link String#String(char[])} and
      * {@link String#getBytes(String)}.
      *
      * @param data  the char array to write, do not modify during output,
      * null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static void write(final char[] data, final OutputStream output, final Charset encoding) throws IOException {
         if (data != null) {
             output.write(new String(data).getBytes(Charsets.toCharset(encoding)));
         }
     }
 
     /**
      * Writes chars from a <code>char[]</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method uses {@link String#String(char[])} and
      * {@link String#getBytes(String)}.
      *
      * @param data  the char array to write, do not modify during output,
      * null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static void write(final char[] data, final OutputStream output, final String encoding)
             throws IOException {
         write(data, output, Charsets.toCharset(encoding));
     }
 
     // write CharSequence
     //-----------------------------------------------------------------------
     /**
      * Writes chars from a <code>CharSequence</code> to a <code>Writer</code>.
      *
      * @param data  the <code>CharSequence</code> to write, null ignored
      * @param output  the <code>Writer</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 2.0
      */
     public static void write(final CharSequence data, final Writer output) throws IOException {
         if (data != null) {
             write(data.toString(), output);
         }
     }
 
     /**
      * Writes chars from a <code>CharSequence</code> to bytes on an
      * <code>OutputStream</code> using the default character encoding of the
      * platform.
      * <p>
      * This method uses {@link String#getBytes()}.
      *
      * @param data  the <code>CharSequence</code> to write, null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 2.0
      * @deprecated 2.5 use {@link #write(CharSequence, OutputStream, Charset)} instead
      */
     @Deprecated
     public static void write(final CharSequence data, final OutputStream output)
             throws IOException {
         write(data, output, Charset.defaultCharset());
     }
 
     /**
      * Writes chars from a <code>CharSequence</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding.
      * <p>
      * This method uses {@link String#getBytes(String)}.
      *
      * @param data  the <code>CharSequence</code> to write, null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static void write(final CharSequence data, final OutputStream output, final Charset encoding) throws IOException {
         if (data != null) {
             write(data.toString(), output, encoding);
         }
     }
 
     /**
      * Writes chars from a <code>CharSequence</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method uses {@link String#getBytes(String)}.
      *
      * @param data  the <code>CharSequence</code> to write, null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 2.0
      */
     public static void write(final CharSequence data, final OutputStream output, final String encoding) throws IOException {
         write(data, output, Charsets.toCharset(encoding));
     }
 
     // write String
     //-----------------------------------------------------------------------
     /**
      * Writes chars from a <code>String</code> to a <code>Writer</code>.
      *
      * @param data  the <code>String</code> to write, null ignored
      * @param output  the <code>Writer</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static void write(final String data, final Writer output) throws IOException {
         if (data != null) {
             output.write(data);
         }
     }
 
     /**
      * Writes chars from a <code>String</code> to bytes on an
      * <code>OutputStream</code> using the default character encoding of the
      * platform.
      * <p>
      * This method uses {@link String#getBytes()}.
      *
      * @param data  the <code>String</code> to write, null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #write(String, OutputStream, Charset)} instead
      */
     @Deprecated
     public static void write(final String data, final OutputStream output)
             throws IOException {
         write(data, output, Charset.defaultCharset());
     }
 
     /**
      * Writes chars from a <code>String</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding.
      * <p>
      * This method uses {@link String#getBytes(String)}.
      *
      * @param data  the <code>String</code> to write, null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static void write(final String data, final OutputStream output, final Charset encoding) throws IOException {
         if (data != null) {
             output.write(data.getBytes(Charsets.toCharset(encoding)));
         }
     }
 
     /**
      * Writes chars from a <code>String</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method uses {@link String#getBytes(String)}.
      *
      * @param data  the <code>String</code> to write, null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static void write(final String data, final OutputStream output, final String encoding)
             throws IOException {
         write(data, output, Charsets.toCharset(encoding));
     }
 
     // write StringBuffer
     //-----------------------------------------------------------------------
     /**
      * Writes chars from a <code>StringBuffer</code> to a <code>Writer</code>.
      *
      * @param data  the <code>StringBuffer</code> to write, null ignored
      * @param output  the <code>Writer</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated replaced by write(CharSequence, Writer)
      */
     @Deprecated
     public static void write(final StringBuffer data, final Writer output)
             throws IOException {
         if (data != null) {
             output.write(data.toString());
         }
     }
 
     /**
      * Writes chars from a <code>StringBuffer</code> to bytes on an
      * <code>OutputStream</code> using the default character encoding of the
      * platform.
      * <p>
      * This method uses {@link String#getBytes()}.
      *
      * @param data  the <code>StringBuffer</code> to write, null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated replaced by write(CharSequence, OutputStream)
      */
     @Deprecated
     public static void write(final StringBuffer data, final OutputStream output)
             throws IOException {
         write(data, output, (String) null);
     }
 
     /**
      * Writes chars from a <code>StringBuffer</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method uses {@link String#getBytes(String)}.
      *
      * @param data  the <code>StringBuffer</code> to write, null ignored
      * @param output  the <code>OutputStream</code> to write to
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if output is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      * @deprecated replaced by write(CharSequence, OutputStream, String)
      */
     @Deprecated
     public static void write(final StringBuffer data, final OutputStream output, final String encoding) throws IOException {
         if (data != null) {
             output.write(data.toString().getBytes(Charsets.toCharset(encoding)));
         }
     }
 
     // writeLines
     //-----------------------------------------------------------------------
     /**
      * Writes the <code>toString()</code> value of each item in a collection to
      * an <code>OutputStream</code> line by line, using the default character
      * encoding of the platform and the specified line ending.
      *
      * @param lines  the lines to write, null entries produce blank lines
      * @param lineEnding  the line separator to use, null is system default
      * @param output  the <code>OutputStream</code> to write to, not null, not closed
      * @throws NullPointerException if the output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #writeLines(Collection, String, OutputStream, Charset)} instead
      */
     @Deprecated
     public static void writeLines(final Collection<?> lines, final String lineEnding,
             final OutputStream output) throws IOException {
         writeLines(lines, lineEnding, output, Charset.defaultCharset());
     }
 
     /**
      * Writes the <code>toString()</code> value of each item in a collection to
      * an <code>OutputStream</code> line by line, using the specified character
      * encoding and the specified line ending.
      *
      * @param lines  the lines to write, null entries produce blank lines
      * @param lineEnding  the line separator to use, null is system default
      * @param output  the <code>OutputStream</code> to write to, not null, not closed
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if the output is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static void writeLines(final Collection<?> lines, String lineEnding, final OutputStream output, final Charset encoding)
             throws IOException {
         if (lines == null) {
             return;
         }
         if (lineEnding == null) {
             lineEnding = LINE_SEPARATOR;
         }
         final Charset cs = Charsets.toCharset(encoding);
         for (final Object line : lines) {
             if (line != null) {
                 output.write(line.toString().getBytes(cs));
             }
             output.write(lineEnding.getBytes(cs));
         }
     }
 
     /**
      * Writes the <code>toString()</code> value of each item in a collection to
      * an <code>OutputStream</code> line by line, using the specified character
      * encoding and the specified line ending.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      *
      * @param lines  the lines to write, null entries produce blank lines
      * @param lineEnding  the line separator to use, null is system default
      * @param output  the <code>OutputStream</code> to write to, not null, not closed
      * @param encoding  the encoding to use, null means platform default
      * @throws NullPointerException if the output is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static void writeLines(final Collection<?> lines, final String lineEnding,
             final OutputStream output, final String encoding) throws IOException {
         writeLines(lines, lineEnding, output, Charsets.toCharset(encoding));
     }
 
     /**
      * Writes the <code>toString()</code> value of each item in a collection to
      * a <code>Writer</code> line by line, using the specified line ending.
      *
      * @param lines  the lines to write, null entries produce blank lines
      * @param lineEnding  the line separator to use, null is system default
      * @param writer  the <code>Writer</code> to write to, not null, not closed
      * @throws NullPointerException if the input is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static void writeLines(final Collection<?> lines, String lineEnding,
             final Writer writer) throws IOException {
         if (lines == null) {
             return;
         }
         if (lineEnding == null) {
             lineEnding = LINE_SEPARATOR;
         }
         for (final Object line : lines) {
             if (line != null) {
                 writer.write(line.toString());
             }
             writer.write(lineEnding);
         }
     }
 
     // copy from InputStream
     //-----------------------------------------------------------------------
     /**
      * Copies bytes from an <code>InputStream</code> to an
      * <code>OutputStream</code>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * <p>
      * Large streams (over 2GB) will return a bytes copied value of
      * <code>-1</code> after the copy has completed since the correct
      * number of bytes cannot be returned as an int. For large streams
      * use the <code>copyLarge(InputStream, OutputStream)</code> method.
      *
      * @param input  the <code>InputStream</code> to read from
      * @param output  the <code>OutputStream</code> to write to
      * @return the number of bytes copied, or -1 if &gt; Integer.MAX_VALUE
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static int copy(final InputStream input, final OutputStream output) throws IOException {
         final long count = copyLarge(input, output);
         if (count > Integer.MAX_VALUE) {
             return -1;
         }
         return (int) count;
     }
 
     /**
      * Copies bytes from an <code>InputStream</code> to an <code>OutputStream</code> using an internal buffer of the
      * given size.
      * <p>
      * This method buffers the input internally, so there is no need to use a <code>BufferedInputStream</code>.
      * <p>
      *
      * @param input
      *            the <code>InputStream</code> to read from
      * @param output
      *            the <code>OutputStream</code> to write to
      * @param bufferSize
      *            the bufferSize used to copy from the input to the output
      * @return the number of bytes copied
      * @throws NullPointerException
      *             if the input or output is null
      * @throws IOException
      *             if an I/O error occurs
      * @since 2.5
      */
     public static long copy(final InputStream input, final OutputStream output, final int bufferSize) throws IOException {
         return copyLarge(input, output, new byte[bufferSize]);
     }
 
     /**
      * Copies bytes from a large (over 2GB) <code>InputStream</code> to an
      * <code>OutputStream</code>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * <p>
      * The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
      *
      * @param input  the <code>InputStream</code> to read from
      * @param output  the <code>OutputStream</code> to write to
      * @return the number of bytes copied
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 1.3
      */
     public static long copyLarge(final InputStream input, final OutputStream output)
             throws IOException {
         return copy(input, output, DEFAULT_BUFFER_SIZE);
     }
 
     /**
      * Copies bytes from a large (over 2GB) <code>InputStream</code> to an
      * <code>OutputStream</code>.
      * <p>
      * This method uses the provided buffer, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * <p>
      *
      * @param input  the <code>InputStream</code> to read from
      * @param output  the <code>OutputStream</code> to write to
      * @param buffer the buffer to use for the copy
      * @return the number of bytes copied
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 2.2
      */
     public static long copyLarge(final InputStream input, final OutputStream output, final byte[] buffer)
             throws IOException {
         long count = 0;
         int n = 0;
         while (EOF != (n = input.read(buffer))) {
             output.write(buffer, 0, n);
             count += n;
         }
         return count;
     }
 
     /**
      * Copies some or all bytes from a large (over 2GB) <code>InputStream</code> to an
      * <code>OutputStream</code>, optionally skipping input bytes.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * </p>
      * <p>
      * Note that the implementation uses {@link #skip(InputStream, long)}.
      * This means that the method may be considerably less efficient than using the actual skip implementation,
      * this is done to guarantee that the correct number of characters are skipped.
      * </p>
      * The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
      *
      * @param input  the <code>InputStream</code> to read from
      * @param output  the <code>OutputStream</code> to write to
      * @param inputOffset : number of bytes to skip from input before copying
      *         -ve values are ignored
      * @param length : number of bytes to copy. -ve means all
      * @return the number of bytes copied
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 2.2
      */
     public static long copyLarge(final InputStream input, final OutputStream output, final long inputOffset, final long length)
             throws IOException {
         return copyLarge(input, output, inputOffset, length, new byte[DEFAULT_BUFFER_SIZE]);
     }
 
     /**
      * Copies some or all bytes from a large (over 2GB) <code>InputStream</code> to an
      * <code>OutputStream</code>, optionally skipping input bytes.
      * <p>
      * This method uses the provided buffer, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * </p>
      * <p>
      * Note that the implementation uses {@link #skip(InputStream, long)}.
      * This means that the method may be considerably less efficient than using the actual skip implementation,
      * this is done to guarantee that the correct number of characters are skipped.
      * </p>
      *
      * @param input  the <code>InputStream</code> to read from
      * @param output  the <code>OutputStream</code> to write to
      * @param inputOffset : number of bytes to skip from input before copying
      *         -ve values are ignored
      * @param length : number of bytes to copy. -ve means all
      * @param buffer the buffer to use for the copy
      *
      * @return the number of bytes copied
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 2.2
      */
     public static long copyLarge(final InputStream input, final OutputStream output,
             final long inputOffset, final long length, final byte[] buffer)  throws IOException {
         if (inputOffset > 0) {
             skipFully(input, inputOffset);
         }
         if (length == 0) {
             return 0;
         }
         final int bufferLength = buffer.length;
         int bytesToRead = bufferLength;
         if (length > 0 && length < bufferLength) {
             bytesToRead = (int) length;
         }
         int read;
         long totalRead = 0;
         while (bytesToRead > 0 && EOF != (read = input.read(buffer, 0, bytesToRead))) {
             output.write(buffer, 0, read);
             totalRead += read;
             if (length > 0) { // only adjust length if not reading to the end
                 // Note the cast must work because buffer.length is an integer
                 bytesToRead = (int) Math.min(length - totalRead, bufferLength);
             }
         }
         return totalRead;
     }
 
     /**
      * Copies bytes from an <code>InputStream</code> to chars on a
      * <code>Writer</code> using the default character encoding of the platform.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * <p>
      * This method uses {@link InputStreamReader}.
      *
      * @param input  the <code>InputStream</code> to read from
      * @param output  the <code>Writer</code> to write to
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #copy(InputStream, Writer, Charset)} instead
      */
     @Deprecated
     public static void copy(final InputStream input, final Writer output)
             throws IOException {
         copy(input, output, Charset.defaultCharset());
     }
 
     /**
      * Copies bytes from an <code>InputStream</code> to chars on a
      * <code>Writer</code> using the specified character encoding.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * <p>
      * This method uses {@link InputStreamReader}.
      *
      * @param input  the <code>InputStream</code> to read from
      * @param output  the <code>Writer</code> to write to
      * @param inputEncoding  the encoding to use for the input stream, null means platform default
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static void copy(final InputStream input, final Writer output, final Charset inputEncoding) throws IOException {
         final InputStreamReader in = new InputStreamReader(input, Charsets.toCharset(inputEncoding));
         copy(in, output);
     }
 
     /**
      * Copies bytes from an <code>InputStream</code> to chars on a
      * <code>Writer</code> using the specified character encoding.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedInputStream</code>.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * This method uses {@link InputStreamReader}.
      *
      * @param input  the <code>InputStream</code> to read from
      * @param output  the <code>Writer</code> to write to
      * @param inputEncoding  the encoding to use for the InputStream, null means platform default
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static void copy(final InputStream input, final Writer output, final String inputEncoding) throws IOException {
         copy(input, output, Charsets.toCharset(inputEncoding));
     }
 
     // copy from Reader
     //-----------------------------------------------------------------------
     /**
      * Copies chars from a <code>Reader</code> to a <code>Writer</code>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      * <p>
      * Large streams (over 2GB) will return a chars copied value of
      * <code>-1</code> after the copy has completed since the correct
      * number of chars cannot be returned as an int. For large streams
      * use the <code>copyLarge(Reader, Writer)</code> method.
      *
      * @param input  the <code>Reader</code> to read from
      * @param output  the <code>Writer</code> to write to
      * @return the number of characters copied, or -1 if &gt; Integer.MAX_VALUE
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static int copy(final Reader input, final Writer output) throws IOException {
         final long count = copyLarge(input, output);
         if (count > Integer.MAX_VALUE) {
             return -1;
         }
         return (int) count;
     }
 
     /**
      * Copies chars from a large (over 2GB) <code>Reader</code> to a <code>Writer</code>.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      * <p>
      * The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
      *
      * @param input  the <code>Reader</code> to read from
      * @param output  the <code>Writer</code> to write to
      * @return the number of characters copied
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 1.3
      */
     public static long copyLarge(final Reader input, final Writer output) throws IOException {
         return copyLarge(input, output, new char[DEFAULT_BUFFER_SIZE]);
     }
 
     /**
      * Copies chars from a large (over 2GB) <code>Reader</code> to a <code>Writer</code>.
      * <p>
      * This method uses the provided buffer, so there is no need to use a
      * <code>BufferedReader</code>.
      * <p>
      *
      * @param input  the <code>Reader</code> to read from
      * @param output  the <code>Writer</code> to write to
      * @param buffer the buffer to be used for the copy
      * @return the number of characters copied
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 2.2
      */
     public static long copyLarge(final Reader input, final Writer output, final char [] buffer) throws IOException {
         long count = 0;
         int n = 0;
         while (EOF != (n = input.read(buffer))) {
             output.write(buffer, 0, n);
             count += n;
         }
         return count;
     }
 
     /**
      * Copies some or all chars from a large (over 2GB) <code>InputStream</code> to an
      * <code>OutputStream</code>, optionally skipping input chars.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      * <p>
      * The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
      *
      * @param input  the <code>Reader</code> to read from
      * @param output  the <code>Writer</code> to write to
      * @param inputOffset : number of chars to skip from input before copying
      *         -ve values are ignored
      * @param length : number of chars to copy. -ve means all
      * @return the number of chars copied
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 2.2
      */
     public static long copyLarge(final Reader input, final Writer output, final long inputOffset, final long length)
             throws IOException {
         return  copyLarge(input, output, inputOffset, length, new char[DEFAULT_BUFFER_SIZE]);
     }
 
     /**
      * Copies some or all chars from a large (over 2GB) <code>InputStream</code> to an
      * <code>OutputStream</code>, optionally skipping input chars.
      * <p>
      * This method uses the provided buffer, so there is no need to use a
      * <code>BufferedReader</code>.
      * <p>
      *
      * @param input  the <code>Reader</code> to read from
      * @param output  the <code>Writer</code> to write to
      * @param inputOffset : number of chars to skip from input before copying
      *         -ve values are ignored
      * @param length : number of chars to copy. -ve means all
      * @param buffer the buffer to be used for the copy
      * @return the number of chars copied
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 2.2
      */
     public static long copyLarge(final Reader input, final Writer output, final long inputOffset, final long length, final char [] buffer)
             throws IOException {
         if (inputOffset > 0) {
             skipFully(input, inputOffset);
         }
         if (length == 0) {
             return 0;
         }
         int bytesToRead = buffer.length;
         if (length > 0 && length < buffer.length) {
             bytesToRead = (int) length;
         }
         int read;
         long totalRead = 0;
         while (bytesToRead > 0 && EOF != (read = input.read(buffer, 0, bytesToRead))) {
             output.write(buffer, 0, read);
             totalRead += read;
             if (length > 0) { // only adjust length if not reading to the end
                 // Note the cast must work because buffer.length is an integer
                 bytesToRead = (int) Math.min(length - totalRead, buffer.length);
             }
         }
         return totalRead;
     }
 
     /**
      * Copies chars from a <code>Reader</code> to bytes on an
      * <code>OutputStream</code> using the default character encoding of the
      * platform, and calling flush.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      * <p>
      * Due to the implementation of OutputStreamWriter, this method performs a
      * flush.
      * <p>
      * This method uses {@link OutputStreamWriter}.
      *
      * @param input  the <code>Reader</code> to read from
      * @param output  the <code>OutputStream</code> to write to
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #copy(Reader, OutputStream, Charset)} instead
      */
     @Deprecated
     public static void copy(final Reader input, final OutputStream output)
             throws IOException {
         copy(input, output, Charset.defaultCharset());
     }
 
     /**
      * Copies chars from a <code>Reader</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding, and
      * calling flush.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      * </p>
      * <p>
      * Due to the implementation of OutputStreamWriter, this method performs a
      * flush.
      * </p>
      * <p>
      * This method uses {@link OutputStreamWriter}.
      * </p>
      *
      * @param input  the <code>Reader</code> to read from
      * @param output  the <code>OutputStream</code> to write to
      * @param outputEncoding  the encoding to use for the OutputStream, null means platform default
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @since 2.3
      */
     public static void copy(final Reader input, final OutputStream output, final Charset outputEncoding) throws IOException {
         final OutputStreamWriter out = new OutputStreamWriter(output, Charsets.toCharset(outputEncoding));
         copy(input, out);
         // XXX Unless anyone is planning on rewriting OutputStreamWriter,
         // we have to flush here.
         out.flush();
     }
 
     /**
      * Copies chars from a <code>Reader</code> to bytes on an
      * <code>OutputStream</code> using the specified character encoding, and
      * calling flush.
      * <p>
      * This method buffers the input internally, so there is no need to use a
      * <code>BufferedReader</code>.
      * <p>
      * Character encoding names can be found at
      * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
      * <p>
      * Due to the implementation of OutputStreamWriter, this method performs a
      * flush.
      * <p>
      * This method uses {@link OutputStreamWriter}.
      *
      * @param input  the <code>Reader</code> to read from
      * @param output  the <code>OutputStream</code> to write to
      * @param outputEncoding  the encoding to use for the OutputStream, null means platform default
      * @throws NullPointerException if the input or output is null
      * @throws IOException if an I/O error occurs
      * @throws UnsupportedCharsetException
      *             thrown instead of {@link UnsupportedEncodingException} in version 2.2 if the encoding is not
      *             supported.
      * @since 1.1
      */
     public static void copy(final Reader input, final OutputStream output, final String outputEncoding) throws IOException {
         copy(input, output, Charsets.toCharset(outputEncoding));
     }
 
     // content equals
     //-----------------------------------------------------------------------
     /**
      * Compares the contents of two Streams to determine if they are equal or
      * not.
      * <p>
      * This method buffers the input internally using
      * <code>BufferedInputStream</code> if they are not already buffered.
      *
      * @param input1  the first stream
      * @param input2  the second stream
      * @return true if the content of the streams are equal or they both don't
      * exist, false otherwise
      * @throws NullPointerException if either input is null
      * @throws IOException if an I/O error occurs
      */
     public static boolean contentEquals(InputStream input1, InputStream input2)
             throws IOException {
         if (input1 == input2) {
             return true;
         }
         if (!(input1 instanceof BufferedInputStream)) {
             input1 = new BufferedInputStream(input1);
         }
         if (!(input2 instanceof BufferedInputStream)) {
             input2 = new BufferedInputStream(input2);
         }
 
         int ch = input1.read();
         while (EOF != ch) {
             final int ch2 = input2.read();
             if (ch != ch2) {
                 return false;
             }
             ch = input1.read();
         }
 
         final int ch2 = input2.read();
         return ch2 == EOF;
     }
 
     /**
      * Compares the contents of two Readers to determine if they are equal or
      * not.
      * <p>
      * This method buffers the input internally using
      * <code>BufferedReader</code> if they are not already buffered.
      *
      * @param input1  the first reader
      * @param input2  the second reader
      * @return true if the content of the readers are equal or they both don't
      * exist, false otherwise
      * @throws NullPointerException if either input is null
      * @throws IOException if an I/O error occurs
      * @since 1.1
      */
     public static boolean contentEquals(Reader input1, Reader input2)
             throws IOException {
         if (input1 == input2) {
             return true;
         }
 
         input1 = toBufferedReader(input1);
         input2 = toBufferedReader(input2);
 
         int ch = input1.read();
         while (EOF != ch) {
             final int ch2 = input2.read();
             if (ch != ch2) {
                 return false;
             }
             ch = input1.read();
         }
 
         final int ch2 = input2.read();
         return ch2 == EOF;
     }
 
     /**
      * Compares the contents of two Readers to determine if they are equal or
      * not, ignoring EOL characters.
      * <p>
      * This method buffers the input internally using
      * <code>BufferedReader</code> if they are not already buffered.
      *
      * @param input1  the first reader
      * @param input2  the second reader
      * @return true if the content of the readers are equal (ignoring EOL differences),  false otherwise
      * @throws NullPointerException if either input is null
      * @throws IOException if an I/O error occurs
      * @since 2.2
      */
     public static boolean contentEqualsIgnoreEOL(final Reader input1, final Reader input2)
             throws IOException {
         if (input1 == input2) {
             return true;
         }
         final BufferedReader br1 = toBufferedReader(input1);
         final BufferedReader br2 = toBufferedReader(input2);
 
         String line1 = br1.readLine();
         String line2 = br2.readLine();
         while (line1 != null && line2 != null && line1.equals(line2)) {
             line1 = br1.readLine();
             line2 = br2.readLine();
         }
         return line1 == null ? line2 == null ? true : false : line1.equals(line2);
     }
 
     /**
      * Skips bytes from an input byte stream.
      * This implementation guarantees that it will read as many bytes
      * as possible before giving up; this may not always be the case for
      * skip() implementations in subclasses of {@link InputStream}.
      * <p>
      * Note that the implementation uses {@link InputStream#read(byte[], int, int)} rather
      * than delegating to {@link InputStream#skip(long)}.
      * This means that the method may be considerably less efficient than using the actual skip implementation,
      * this is done to guarantee that the correct number of bytes are skipped.
      * </p>
      *
      *
      * @param input byte stream to skip
      * @param toSkip number of bytes to skip.
      * @return number of bytes actually skipped.
      *
      * @see InputStream#skip(long)
      * @see <a href="https://issues.apache.org/jira/browse/IO-203">IO-203 - Add skipFully() method for InputStreams</a>
      *
      * @throws IOException if there is a problem reading the file
      * @throws IllegalArgumentException if toSkip is negative
      * @since 2.0
      */
     public static long skip(final InputStream input, final long toSkip) throws IOException {
         if (toSkip < 0) {
             throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
         }
         /*
          * N.B. no need to synchronize this because: - we don't care if the buffer is created multiple times (the data
          * is ignored) - we always use the same size buffer, so if it it is recreated it will still be OK (if the buffer
          * size were variable, we would need to synch. to ensure some other thread did not create a smaller one)
          */
         if (SKIP_BYTE_BUFFER == null) {
             SKIP_BYTE_BUFFER = new byte[SKIP_BUFFER_SIZE];
         }
         long remain = toSkip;
         while (remain > 0) {
             // See https://issues.apache.org/jira/browse/IO-203 for why we use read() rather than delegating to skip()
             final long n = input.read(SKIP_BYTE_BUFFER, 0, (int) Math.min(remain, SKIP_BUFFER_SIZE));
             if (n < 0) { // EOF
                 break;
             }
             remain -= n;
         }
         return toSkip - remain;
     }
 
     /**
      * Skips bytes from a ReadableByteChannel.
      * This implementation guarantees that it will read as many bytes
      * as possible before giving up.
      *
      * @param input ReadableByteChannel to skip
      * @param toSkip number of bytes to skip.
      * @return number of bytes actually skipped.
      *
      * @throws IOException if there is a problem reading the ReadableByteChannel
      * @throws IllegalArgumentException if toSkip is negative
      * @since 2.5
      */
     public static long skip(final ReadableByteChannel input, final long toSkip) throws IOException {
         if (toSkip < 0) {
             throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
         }
         final ByteBuffer skipByteBuffer = ByteBuffer.allocate((int) Math.min(toSkip, SKIP_BUFFER_SIZE));
         long remain = toSkip;
         while (remain > 0) {
             skipByteBuffer.position(0);
             skipByteBuffer.limit((int) Math.min(remain, SKIP_BUFFER_SIZE));
             final int n = input.read(skipByteBuffer);
             if (n == EOF) {
                 break;
             }
             remain -= n;
         }
         return toSkip - remain;
     }
 
     /**
      * Skips characters from an input character stream.
      * This implementation guarantees that it will read as many characters
      * as possible before giving up; this may not always be the case for
      * skip() implementations in subclasses of {@link Reader}.
      * <p>
      * Note that the implementation uses {@link Reader#read(char[], int, int)} rather
      * than delegating to {@link Reader#skip(long)}.
      * This means that the method may be considerably less efficient than using the actual skip implementation,
      * this is done to guarantee that the correct number of characters are skipped.
      * </p>
      *
      * @param input character stream to skip
      * @param toSkip number of characters to skip.
      * @return number of characters actually skipped.
      *
      * @see Reader#skip(long)
      * @see <a href="https://issues.apache.org/jira/browse/IO-203">IO-203 - Add skipFully() method for InputStreams</a>
      *
      * @throws IOException if there is a problem reading the file
      * @throws IllegalArgumentException if toSkip is negative
      * @since 2.0
      */
     public static long skip(final Reader input, final long toSkip) throws IOException {
         if (toSkip < 0) {
             throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
         }
         /*
          * N.B. no need to synchronize this because: - we don't care if the buffer is created multiple times (the data
          * is ignored) - we always use the same size buffer, so if it it is recreated it will still be OK (if the buffer
          * size were variable, we would need to synch. to ensure some other thread did not create a smaller one)
          */
         if (SKIP_CHAR_BUFFER == null) {
             SKIP_CHAR_BUFFER = new char[SKIP_BUFFER_SIZE];
         }
         long remain = toSkip;
         while (remain > 0) {
             // See https://issues.apache.org/jira/browse/IO-203 for why we use read() rather than delegating to skip()
             final long n = input.read(SKIP_CHAR_BUFFER, 0, (int) Math.min(remain, SKIP_BUFFER_SIZE));
             if (n < 0) { // EOF
                 break;
             }
             remain -= n;
         }
         return toSkip - remain;
     }
 
     /**
      * Skips the requested number of bytes or fail if there are not enough left.
      * <p>
      * This allows for the possibility that {@link InputStream#skip(long)} may
      * not skip as many bytes as requested (most likely because of reaching EOF).
      * <p>
      * Note that the implementation uses {@link #skip(InputStream, long)}.
      * This means that the method may be considerably less efficient than using the actual skip implementation,
      * this is done to guarantee that the correct number of characters are skipped.
      * </p>
      *
      * @param input stream to skip
      * @param toSkip the number of bytes to skip
      * @see InputStream#skip(long)
      *
      * @throws IOException if there is a problem reading the file
      * @throws IllegalArgumentException if toSkip is negative
      * @throws EOFException if the number of bytes skipped was incorrect
      * @since 2.0
      */
     public static void skipFully(final InputStream input, final long toSkip) throws IOException {
         if (toSkip < 0) {
             throw new IllegalArgumentException("Bytes to skip must not be negative: " + toSkip);
         }
         final long skipped = skip(input, toSkip);
         if (skipped != toSkip) {
             throw new EOFException("Bytes to skip: " + toSkip + " actual: " + skipped);
         }
     }
 
     /**
      * Skips the requested number of bytes or fail if there are not enough left.
      *
      * @param input ReadableByteChannel to skip
      * @param toSkip the number of bytes to skip
      *
      * @throws IOException if there is a problem reading the ReadableByteChannel
      * @throws IllegalArgumentException if toSkip is negative
      * @throws EOFException if the number of bytes skipped was incorrect
      * @since 2.5
      */
     public static void skipFully(final ReadableByteChannel input, final long toSkip) throws IOException {
         if (toSkip < 0) {
             throw new IllegalArgumentException("Bytes to skip must not be negative: " + toSkip);
         }
         final long skipped = skip(input, toSkip);
         if (skipped != toSkip) {
             throw new EOFException("Bytes to skip: " + toSkip + " actual: " + skipped);
         }
     }
 
     /**
      * Skips the requested number of characters or fail if there are not enough left.
      * <p>
      * This allows for the possibility that {@link Reader#skip(long)} may
      * not skip as many characters as requested (most likely because of reaching EOF).
      * <p>
      * Note that the implementation uses {@link #skip(Reader, long)}.
      * This means that the method may be considerably less efficient than using the actual skip implementation,
      * this is done to guarantee that the correct number of characters are skipped.
      * </p>
      *
      * @param input stream to skip
      * @param toSkip the number of characters to skip
      * @see Reader#skip(long)
      *
      * @throws IOException if there is a problem reading the file
      * @throws IllegalArgumentException if toSkip is negative
      * @throws EOFException if the number of characters skipped was incorrect
      * @since 2.0
      */
     public static void skipFully(final Reader input, final long toSkip) throws IOException {
         final long skipped = skip(input, toSkip);
         if (skipped != toSkip) {
             throw new EOFException("Chars to skip: " + toSkip + " actual: " + skipped);
         }
     }
 
 
     /**
      * Reads characters from an input character stream.
      * This implementation guarantees that it will read as many characters
      * as possible before giving up; this may not always be the case for
      * subclasses of {@link Reader}.
      *
      * @param input where to read input from
      * @param buffer destination
      * @param offset initial offset into buffer
      * @param length length to read, must be >= 0
      * @return actual length read; may be less than requested if EOF was reached
      * @throws IOException if a read error occurs
      * @since 2.2
      */
     public static int read(final Reader input, final char[] buffer, final int offset, final int length) throws IOException {
         if (length < 0) {
             throw new IllegalArgumentException("Length must not be negative: " + length);
         }
         int remaining = length;
         while (remaining > 0) {
             final int location = length - remaining;
             final int count = input.read(buffer, offset + location, remaining);
             if (EOF == count) { // EOF
                 break;
             }
             remaining -= count;
         }
         return length - remaining;
     }
 
     /**
      * Reads characters from an input character stream.
      * This implementation guarantees that it will read as many characters
      * as possible before giving up; this may not always be the case for
      * subclasses of {@link Reader}.
      *
      * @param input where to read input from
      * @param buffer destination
      * @return actual length read; may be less than requested if EOF was reached
      * @throws IOException if a read error occurs
      * @since 2.2
      */
     public static int read(final Reader input, final char[] buffer) throws IOException {
         return read(input, buffer, 0, buffer.length);
     }
 
     /**
      * Reads bytes from an input stream.
      * This implementation guarantees that it will read as many bytes
      * as possible before giving up; this may not always be the case for
      * subclasses of {@link InputStream}.
      *
      * @param input where to read input from
      * @param buffer destination
      * @param offset initial offset into buffer
      * @param length length to read, must be >= 0
      * @return actual length read; may be less than requested if EOF was reached
      * @throws IOException if a read error occurs
      * @since 2.2
      */
     public static int read(final InputStream input, final byte[] buffer, final int offset, final int length) throws IOException {
         if (length < 0) {
             throw new IllegalArgumentException("Length must not be negative: " + length);
         }
         int remaining = length;
         while (remaining > 0) {
             final int location = length - remaining;
             final int count = input.read(buffer, offset + location, remaining);
             if (EOF == count) { // EOF
                 break;
             }
             remaining -= count;
         }
         return length - remaining;
     }
 
     /**
      * Reads bytes from an input stream.
      * This implementation guarantees that it will read as many bytes
      * as possible before giving up; this may not always be the case for
      * subclasses of {@link InputStream}.
      *
      * @param input where to read input from
      * @param buffer destination
      * @return actual length read; may be less than requested if EOF was reached
      * @throws IOException if a read error occurs
      * @since 2.2
      */
     public static int read(final InputStream input, final byte[] buffer) throws IOException {
         return read(input, buffer, 0, buffer.length);
     }
 
     /**
      * Reads bytes from a ReadableByteChannel.
      * <p>
      * This implementation guarantees that it will read as many bytes
      * as possible before giving up; this may not always be the case for
      * subclasses of {@link ReadableByteChannel}.
      *
      * @param input the byte channel to read
      * @param buffer byte buffer destination
      * @return the actual length read; may be less than requested if EOF was reached
      * @throws IOException if a read error occurs
      * @since 2.5
      */
     public static int read(final ReadableByteChannel input, final ByteBuffer buffer) throws IOException {
         final int length = buffer.remaining();
         while (buffer.remaining() > 0) {
             final int count = input.read(buffer);
             if (EOF == count) { // EOF
                 break;
             }
         }
         return length - buffer.remaining();
     }
 
     /**
      * Reads the requested number of characters or fail if there are not enough left.
      * <p>
      * This allows for the possibility that {@link Reader#read(char[], int, int)} may
      * not read as many characters as requested (most likely because of reaching EOF).
      *
      * @param input where to read input from
      * @param buffer destination
      * @param offset initial offset into buffer
      * @param length length to read, must be >= 0
      *
      * @throws IOException if there is a problem reading the file
      * @throws IllegalArgumentException if length is negative
      * @throws EOFException if the number of characters read was incorrect
      * @since 2.2
      */
     public static void readFully(final Reader input, final char[] buffer, final int offset, final int length) throws IOException {
         final int actual = read(input, buffer, offset, length);
         if (actual != length) {
             throw new EOFException("Length to read: " + length + " actual: " + actual);
         }
     }
 
     /**
      * Reads the requested number of characters or fail if there are not enough left.
      * <p>
      * This allows for the possibility that {@link Reader#read(char[], int, int)} may
      * not read as many characters as requested (most likely because of reaching EOF).
      *
      * @param input where to read input from
      * @param buffer destination
      *
      * @throws IOException if there is a problem reading the file
      * @throws IllegalArgumentException if length is negative
      * @throws EOFException if the number of characters read was incorrect
      * @since 2.2
      */
     public static void readFully(final Reader input, final char[] buffer) throws IOException {
         readFully(input, buffer, 0, buffer.length);
     }
 
     /**
      * Reads the requested number of bytes or fail if there are not enough left.
      * <p>
      * This allows for the possibility that {@link InputStream#read(byte[], int, int)} may
      * not read as many bytes as requested (most likely because of reaching EOF).
      *
      * @param input where to read input from
      * @param buffer destination
      * @param offset initial offset into buffer
      * @param length length to read, must be >= 0
      *
      * @throws IOException if there is a problem reading the file
      * @throws IllegalArgumentException if length is negative
      * @throws EOFException if the number of bytes read was incorrect
      * @since 2.2
      */
     public static void readFully(final InputStream input, final byte[] buffer, final int offset, final int length) throws IOException {
         final int actual = read(input, buffer, offset, length);
         if (actual != length) {
             throw new EOFException("Length to read: " + length + " actual: " + actual);
         }
     }
 
     /**
      * Reads the requested number of bytes or fail if there are not enough left.
      * <p>
      * This allows for the possibility that {@link InputStream#read(byte[], int, int)} may
      * not read as many bytes as requested (most likely because of reaching EOF).
      *
      * @param input where to read input from
      * @param buffer destination
      *
      * @throws IOException if there is a problem reading the file
      * @throws IllegalArgumentException if length is negative
      * @throws EOFException if the number of bytes read was incorrect
      * @since 2.2
      */
     public static void readFully(final InputStream input, final byte[] buffer) throws IOException {
         readFully(input, buffer, 0, buffer.length);
     }
 
     /**
      * Reads the requested number of bytes or fail if there are not enough left.
      * <p>
      * This allows for the possibility that {@link ReadableByteChannel#read(ByteBuffer)} may
      * not read as many bytes as requested (most likely because of reaching EOF).
      *
      * @param input the byte channel to read
      * @param buffer byte buffer destination
      *
      * @throws IOException if there is a problem reading the file
      * @throws EOFException if the number of bytes read was incorrect
      * @since 2.5
      */
     public static void readFully(final ReadableByteChannel input, final ByteBuffer buffer) throws IOException {
         final int expected = buffer.remaining();
         final int actual = read(input, buffer);
         if (actual != expected) {
             throw new EOFException("Length to read: " + expected + " actual: " + actual);
         }
     }
 }