/*
    * 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
    *
    *      https://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.input;
  
  import static org.apache.commons.io.IOUtils.CR;
  import static org.apache.commons.io.IOUtils.EOF;
  import static org.apache.commons.io.IOUtils.LF;
  
  import java.io.ByteArrayOutputStream;
  import java.io.Closeable;
  import java.io.File;
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.io.RandomAccessFile;
  import java.nio.charset.Charset;
  import java.nio.file.Files;
  import java.nio.file.LinkOption;
  import java.nio.file.Path;
  import java.nio.file.attribute.FileTime;
  import java.time.Duration;
  import java.util.Arrays;
  import java.util.Objects;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.io.ThreadUtils;
  import org.apache.commons.io.build.AbstractOrigin;
  import org.apache.commons.io.build.AbstractStreamBuilder;
  import org.apache.commons.io.file.PathUtils;
  import org.apache.commons.io.file.attribute.FileTimes;
  
  /**
   * Simple implementation of the Unix "tail -f" functionality.
   * <p>
   * To build an instance, use {@link Builder}.
   * </p>
   * <h2>1. Create a TailerListener implementation</h2>
   * <p>
   * First you need to create a {@link TailerListener} implementation; ({@link TailerListenerAdapter} is provided for
   * convenience so that you don't have to implement every method).
   * </p>
   * <p>
   * For example:
   * </p>
   * <pre>
   * public class MyTailerListener extends TailerListenerAdapter {
   *     public void handle(String line) {
   *         System.out.println(line);
   *     }
   * }
   * </pre>
   * <h2>2. Using a Tailer</h2>
   * <p>
   * You can create and use a Tailer in one of three ways:
   * </p>
   * <ul>
   * <li>Using a {@link Builder}</li>
   * <li>Using an {@link java.util.concurrent.Executor}</li>
   * <li>Using a {@link Thread}</li>
   * </ul>
   * <p>
   * An example of each is shown below.
   * </p>
   * <h3>2.1 Using a Builder</h3>
   * <pre>
   * TailerListener listener = new MyTailerListener();
   * Tailer tailer = Tailer.builder()
   *   .setFile(file)
   *   .setTailerListener(listener)
   *   .setDelayDuration(delay)
   *   .get();
   * </pre>
   * <h3>2.2 Using an Executor</h3>
   * <pre>
   * TailerListener listener = new MyTailerListener();
   * Tailer tailer = new Tailer(file, listener, delay);
   *
   * // stupid executor impl. for demo purposes
   * Executor executor = new Executor() {
   *     public void execute(Runnable command) {
   *         command.run();
   *     }
   * };
   *
  * executor.execute(tailer);
  * </pre>
  * <h3>2.3 Using a Thread</h3>
  * <pre>
  * TailerListener listener = new MyTailerListener();
  * Tailer tailer = new Tailer(file, listener, delay);
  * Thread thread = new Thread(tailer);
  * thread.setDaemon(true); // optional
  * thread.start();
  * </pre>
  * <h2>3. Stopping a Tailer</h2>
  * <p>
  * Remember to stop the tailer when you have done with it:
  * </p>
  * <pre>
  * tailer.stop();
  * </pre>
  * <h2>4. Interrupting a Tailer</h2>
  * <p>
  * You can interrupt the thread a tailer is running on by calling {@link Thread#interrupt()}.
  * </p>
  * <pre>
  * thread.interrupt();
  * </pre>
  * <p>
  * If you interrupt a tailer, the tailer listener is called with the {@link InterruptedException}.
  * </p>
  * <p>
  * The file is read using the default Charset; this can be overridden if necessary.
  * </p>
  *
  * @see Builder
  * @see TailerListener
  * @see TailerListenerAdapter
  * @since 2.0
  * @since 2.5 Updated behavior and documentation for {@link Thread#interrupt()}.
  * @since 2.12.0 Add {@link Tailable} and {@link RandomAccessResourceBridge} interfaces to tail of files accessed using
  *        alternative libraries such as jCIFS or <a href="https://commons.apache.org/proper/commons-vfs/">Apache Commons
  *        VFS</a>.
  */
 public class Tailer implements Runnable, AutoCloseable {
     // @formatter:off
     /**
      * Builds a new {@link Tailer}.
      *
      * <p>
      * For example:
      * </p>
      * <pre>{@code
      * Tailer t = Tailer.builder()
      *   .setPath(path)
      *   .setCharset(StandardCharsets.UTF_8)
      *   .setDelayDuration(Duration.ofSeconds(1))
      *   .setExecutorService(Executors.newSingleThreadExecutor(Builder::newDaemonThread))
      *   .setReOpen(false)
      *   .setStartThread(true)
      *   .setTailable(tailable)
      *   .setTailerListener(tailerListener)
      *   .setTailFromEnd(false)
      *   .get();}
      * </pre>
      *
      * @see #get()
      * @since 2.12.0
      */
     // @formatter:on
     public static class Builder extends AbstractStreamBuilder<Tailer, Builder> {
 
         private static final Duration DEFAULT_DELAY_DURATION = Duration.ofMillis(DEFAULT_DELAY_MILLIS);
 
         /**
          * Creates a new daemon thread.
          *
          * @param runnable the thread's runnable.
          * @return a new daemon thread.
          */
         private static Thread newDaemonThread(final Runnable runnable) {
             final Thread thread = new Thread(runnable, "commons-io-tailer");
             thread.setDaemon(true);
             return thread;
         }
 
         private Tailable tailable;
         private TailerListener tailerListener;
         private Duration delayDuration = DEFAULT_DELAY_DURATION;
         private boolean tailFromEnd;
         private boolean reOpen;
         private boolean startThread = true;
         private boolean ignoreTouch = DEFAULT_IGNORE_TOUCH;
         private ExecutorService executorService = Executors.newSingleThreadExecutor(Builder::newDaemonThread);
 
         /**
          * Constructs a new builder of {@link Tailer}.
          */
         public Builder() {
             // empty
         }
 
         /**
          * Builds a new {@link Tailer}.
          *
          * <p>
          * This builder uses the following aspects:
          * </p>
          * <ul>
          * <li>{@link #getBufferSize()}</li>
          * <li>{@link #getCharset()}</li>
          * <li>{@link Tailable}</li>
          * <li>{@link TailerListener}</li>
          * <li>delayDuration</li>
          * <li>tailFromEnd</li>
          * <li>reOpen</li>
          * </ul>
          *
          * @return a new instance.
          * @see #getUnchecked()
          */
         @Override
         public Tailer get() {
             final Tailer tailer = new Tailer(this);
             if (startThread) {
                 executorService.submit(tailer);
             }
             return tailer;
         }
 
         /**
          * Sets the delay duration. null resets to the default delay of one second.
          *
          * @param delayDuration the delay between checks of the file for new content.
          * @return {@code this} instance.
          */
         public Builder setDelayDuration(final Duration delayDuration) {
             this.delayDuration = delayDuration != null ? delayDuration : DEFAULT_DELAY_DURATION;
             return this;
         }
 
         /**
          * Sets the executor service to use when startThread is true.
          *
          * @param executorService the executor service to use when startThread is true.
          * @return {@code this} instance.
          */
         public Builder setExecutorService(final ExecutorService executorService) {
             this.executorService = Objects.requireNonNull(executorService, "executorService");
             return this;
         }
 
         /**
          * Sets whether a change in timestamp causes the file to be re-read.
          * <p>
          * Useful when your watched file gets touched (the timestamps is more recent without changing the file) or when a file system updates a timestamp before
          * a file's content. The default (false) re-reads the current file, while true does nothing.
          * </p>
          *
          * @param ignoreTouch Whether a change in timestamp causes the file to be re-read.
          * @return {@code this} instance.
          * @since 2.20.0
          */
         public Builder setIgnoreTouch(final boolean ignoreTouch) {
             this.ignoreTouch = ignoreTouch;
             return this;
         }
 
         /**
          * Sets the origin.
          *
          * @throws UnsupportedOperationException if the origin cannot be converted to a Path.
          */
         @Override
         protected Builder setOrigin(final AbstractOrigin<?, ?> origin) {
             setTailable(new TailablePath(origin.getPath()));
             return super.setOrigin(origin);
         }
 
         /**
          * Sets the re-open behavior.
          *
          * @param reOpen whether to close/reopen the file between chunks
          * @return {@code this} instance.
          */
         public Builder setReOpen(final boolean reOpen) {
             this.reOpen = reOpen;
             return this;
         }
 
         /**
          * Sets the daemon thread startup behavior.
          *
          * @param startThread whether to create a daemon thread automatically.
          * @return {@code this} instance.
          */
         public Builder setStartThread(final boolean startThread) {
             this.startThread = startThread;
             return this;
         }
 
         /**
          * Sets the tailable.
          *
          * @param tailable the tailable.
          * @return {@code this} instance.
          */
         public Builder setTailable(final Tailable tailable) {
             this.tailable = Objects.requireNonNull(tailable, "tailable");
             return this;
         }
 
         /**
          * Sets the listener.
          *
          * @param tailerListener the listener.
          * @return {@code this} instance.
          */
         public Builder setTailerListener(final TailerListener tailerListener) {
             this.tailerListener = Objects.requireNonNull(tailerListener, "tailerListener");
             return this;
         }
 
         /**
          * Sets the tail start behavior.
          *
          * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
          * @return {@code this} instance.
          */
         public Builder setTailFromEnd(final boolean end) {
             this.tailFromEnd = end;
             return this;
         }
     }
 
     /**
      * Bridges random access to a {@link RandomAccessFile}.
      */
     private static final class RandomAccessFileBridge implements RandomAccessResourceBridge {
 
         private final RandomAccessFile randomAccessFile;
 
         private RandomAccessFileBridge(final File file, final String mode) throws FileNotFoundException {
             randomAccessFile = new RandomAccessFile(file, mode);
         }
 
         @Override
         public void close() throws IOException {
             randomAccessFile.close();
         }
 
         @Override
         public long getPointer() throws IOException {
             return randomAccessFile.getFilePointer();
         }
 
         @Override
         public int read(final byte[] b) throws IOException {
             return randomAccessFile.read(b);
         }
 
         @Override
         public void seek(final long position) throws IOException {
             randomAccessFile.seek(position);
         }
 
     }
 
     /**
      * Bridges access to a resource for random access, normally a file. Allows substitution of remote files for example
      * using jCIFS.
      *
      * @since 2.12.0
      */
     public interface RandomAccessResourceBridge extends Closeable {
 
         /**
          * Gets the current offset in this tailable.
          *
          * @return the offset from the beginning of the tailable, in bytes, at which the next read or write occurs.
          * @throws IOException if an I/O error occurs.
          */
         long getPointer() throws IOException;
 
         /**
          * Reads up to {@code b.length} bytes of data from this tailable into an array of bytes. This method blocks until at
          * least one byte of input is available.
          *
          * @param b the buffer into which the data is read.
          * @return the total number of bytes read into the buffer, or {@code -1} if there is no more data because the end of
          *         this tailable has been reached.
          * @throws IOException If the first byte cannot be read for any reason other than end of tailable, or if the random
          *         access tailable has been closed, or if some other I/O error occurs.
          */
         int read(byte[] b) throws IOException;
 
         /**
          * Sets the file-pointer offset, measured from the beginning of this tailable, at which the next read or write occurs.
          * The offset may be set beyond the end of the tailable. Setting the offset beyond the end of the tailable does not
          * change the tailable length. The tailable length will change only by writing after the offset has been set beyond the
          * end of the tailable.
          *
          * @param pos the offset position, measured in bytes from the beginning of the tailable, at which to set the tailable
          *        pointer.
          * @throws IOException if {@code pos} is less than {@code 0} or if an I/O error occurs.
          */
         void seek(long pos) throws IOException;
     }
 
     /**
      * A tailable resource like a file.
      *
      * @since 2.12.0
      */
     public interface Tailable {
 
         /**
          * Creates a random access file stream to read.
          *
          * @param mode the access mode, by default this is for {@link RandomAccessFile}.
          * @return a random access file stream to read.
          * @throws FileNotFoundException if the tailable object does not exist.
          */
         RandomAccessResourceBridge getRandomAccess(String mode) throws FileNotFoundException;
 
         /**
          * Tests if this tailable is newer than the specified {@link FileTime}.
          *
          * @param fileTime the file time reference.
          * @return true if the {@link File} exists and has been modified after the given {@link FileTime}.
          * @throws IOException if an I/O error occurs.
          */
         boolean isNewer(FileTime fileTime) throws IOException;
 
         /**
          * Gets the last modification {@link FileTime}.
          *
          * @return See {@link java.nio.file.Files#getLastModifiedTime(Path, LinkOption...)}.
          * @throws IOException if an I/O error occurs.
          */
         FileTime lastModifiedFileTime() throws IOException;
 
         /**
          * Gets the size of this tailable.
          *
          * @return The size, in bytes, of this tailable, or {@code 0} if the file does not exist. Some operating systems may
          *         return {@code 0} for path names denoting system-dependent entities such as devices or pipes.
          * @throws IOException if an I/O error occurs.
          */
         long size() throws IOException;
     }
 
     /**
      * A tailable for a file {@link Path}.
      */
     private static final class TailablePath implements Tailable {
 
         private final Path path;
         private final LinkOption[] linkOptions;
 
         private TailablePath(final Path path, final LinkOption... linkOptions) {
             this.path = Objects.requireNonNull(path, "path");
             this.linkOptions = linkOptions;
         }
 
         Path getPath() {
             return path;
         }
 
         @Override
         public RandomAccessResourceBridge getRandomAccess(final String mode) throws FileNotFoundException {
             return new RandomAccessFileBridge(path.toFile(), mode);
         }
 
         @Override
         public boolean isNewer(final FileTime fileTime) throws IOException {
             return PathUtils.isNewer(path, fileTime, linkOptions);
         }
 
         @Override
         public FileTime lastModifiedFileTime() throws IOException {
             return Files.getLastModifiedTime(path, linkOptions);
         }
 
         @Override
         public long size() throws IOException {
             return Files.size(path);
         }
 
         @Override
         public String toString() {
             return "TailablePath [file=" + path + ", linkOptions=" + Arrays.toString(linkOptions) + "]";
         }
     }
 
     private static final boolean DEFAULT_IGNORE_TOUCH = false;
 
     private static final int DEFAULT_DELAY_MILLIS = 1000;
 
     private static final String RAF_READ_ONLY_MODE = "r";
 
     /**
      * The the virtual machine's {@linkplain Charset#defaultCharset() default charset} used for reading files.
      */
     private static final Charset DEFAULT_CHARSET = Charset.defaultCharset();
 
     /**
      * Constructs a new {@link Builder}.
      *
      * @return Creates a new {@link Builder}.
      * @since 2.12.0
      */
     public static Builder builder() {
         return new Builder();
     }
 
     /**
      * Creates and starts a Tailer for the given file.
      *
      * @param file the file to follow.
      * @param charset the character set to use for reading the file.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param reOpen whether to close/reopen the file between chunks.
      * @param bufferSize buffer size.
      * @return The new tailer.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public static Tailer create(final File file, final Charset charset, final TailerListener tailerListener, final long delayMillis, final boolean end,
             final boolean reOpen, final int bufferSize) {
         //@formatter:off
         return builder()
                 .setFile(file)
                 .setTailerListener(tailerListener)
                 .setCharset(charset)
                 .setDelayDuration(Duration.ofMillis(delayMillis))
                 .setTailFromEnd(end)
                 .setReOpen(reOpen)
                 .setBufferSize(bufferSize)
                 .get();
         //@formatter:on
     }
 
     /**
      * Creates and starts a Tailer for the given file, starting at the beginning of the file with the default delay of 1.0s
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @return The new tailer.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public static Tailer create(final File file, final TailerListener tailerListener) {
         //@formatter:off
         return builder()
                 .setFile(file)
                 .setTailerListener(tailerListener)
                 .get();
         //@formatter:on
     }
 
     /**
      * Creates and starts a Tailer for the given file, starting at the beginning of the file
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @return The new tailer.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public static Tailer create(final File file, final TailerListener tailerListener, final long delayMillis) {
         //@formatter:off
         return builder()
                 .setFile(file)
                 .setTailerListener(tailerListener)
                 .setDelayDuration(Duration.ofMillis(delayMillis))
                 .get();
         //@formatter:on
     }
 
     /**
      * Creates and starts a Tailer for the given file with default buffer size.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @return The new tailer.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public static Tailer create(final File file, final TailerListener tailerListener, final long delayMillis, final boolean end) {
         //@formatter:off
         return builder()
                 .setFile(file)
                 .setTailerListener(tailerListener)
                 .setDelayDuration(Duration.ofMillis(delayMillis))
                 .setTailFromEnd(end)
                 .get();
         //@formatter:on
     }
 
     /**
      * Creates and starts a Tailer for the given file with default buffer size.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param reOpen whether to close/reopen the file between chunks.
      * @return The new tailer.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public static Tailer create(final File file, final TailerListener tailerListener, final long delayMillis, final boolean end, final boolean reOpen) {
         //@formatter:off
         return builder()
                 .setFile(file)
                 .setTailerListener(tailerListener)
                 .setDelayDuration(Duration.ofMillis(delayMillis))
                 .setTailFromEnd(end)
                 .setReOpen(reOpen)
                 .get();
         //@formatter:on
     }
 
     /**
      * Creates and starts a Tailer for the given file.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param reOpen whether to close/reopen the file between chunks.
      * @param bufferSize buffer size.
      * @return The new tailer.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public static Tailer create(final File file, final TailerListener tailerListener, final long delayMillis, final boolean end, final boolean reOpen,
         final int bufferSize) {
         //@formatter:off
         return builder()
                 .setFile(file)
                 .setTailerListener(tailerListener)
                 .setDelayDuration(Duration.ofMillis(delayMillis))
                 .setTailFromEnd(end)
                 .setReOpen(reOpen)
                 .setBufferSize(bufferSize)
                 .get();
         //@formatter:on
     }
 
     /**
      * Creates and starts a Tailer for the given file.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param bufferSize buffer size.
      * @return The new tailer.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public static Tailer create(final File file, final TailerListener tailerListener, final long delayMillis, final boolean end, final int bufferSize) {
         //@formatter:off
         return builder()
                 .setFile(file)
                 .setTailerListener(tailerListener)
                 .setDelayDuration(Duration.ofMillis(delayMillis))
                 .setTailFromEnd(end)
                 .setBufferSize(bufferSize)
                 .get();
         //@formatter:on
     }
 
     /**
      * Buffer on top of RandomAccessResourceBridge.
      */
     private final byte[] inbuf;
 
     /**
      * The file which will be tailed.
      */
     private final Tailable tailable;
 
     /**
      * The character set that will be used to read the file.
      */
     private final Charset charset;
 
     /**
      * The amount of time to wait for the file to be updated.
      */
     private final Duration delayDuration;
 
     /**
      * Whether to tail from the end or start of file
      */
     private final boolean tailFromEnd;
 
     /**
      * The listener to notify of events when tailing.
      */
     private final TailerListener listener;
 
     /**
      * Whether to close and reopen the file whilst waiting for more input.
      */
     private final boolean reOpen;
 
     /**
      * The tailer will run as long as this value is true.
      */
     private volatile boolean run = true;
 
     /**
      * Whether to ignore a touch on the file, a change in timestamp when the contents stay the same.
      */
     private final boolean ignoreTouch;
 
     /**
      * Creates a Tailer for the given file, with a specified buffer size.
      *
      * @param builder holds construction data.
      */
     private Tailer(final Builder builder) {
         this.tailable = Objects.requireNonNull(builder.tailable, "tailable");
         this.listener = Objects.requireNonNull(builder.tailerListener, "listener");
         this.delayDuration = builder.delayDuration;
         this.tailFromEnd = builder.tailFromEnd;
         this.inbuf = IOUtils.byteArray(builder.getBufferSize());
         // Save and prepare the listener
         listener.init(this);
         this.reOpen = builder.reOpen;
         this.charset = builder.getCharset();
         this.ignoreTouch = builder.ignoreTouch;
     }
 
     /**
      * Creates a Tailer for the given file, with a specified buffer size.
      *
      * @param file the file to follow.
      * @param charset the Charset to be used for reading the file
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param reOpen if true, close and reopen the file between reading chunks
      * @param bufSize Buffer size
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public Tailer(final File file, final Charset charset, final TailerListener tailerListener, final long delayMillis, final boolean end, final boolean reOpen,
             final int bufSize) {
         this(new TailablePath(file.toPath()), charset, tailerListener, Duration.ofMillis(delayMillis), end, reOpen, bufSize, DEFAULT_IGNORE_TOUCH);
     }
 
     /**
      * Creates a Tailer for the given file, starting from the beginning, with the default delay of 1.0s.
      *
      * @param file The file to follow.
      * @param tailerListener the TailerListener to use.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public Tailer(final File file, final TailerListener tailerListener) {
         this(file, tailerListener, DEFAULT_DELAY_MILLIS);
     }
 
     /**
      * Creates a Tailer for the given file, starting from the beginning.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public Tailer(final File file, final TailerListener tailerListener, final long delayMillis) {
         this(file, tailerListener, delayMillis, false);
     }
 
     /**
      * Creates a Tailer for the given file, with a delay other than the default 1.0s.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public Tailer(final File file, final TailerListener tailerListener, final long delayMillis, final boolean end) {
         this(file, tailerListener, delayMillis, end, IOUtils.DEFAULT_BUFFER_SIZE);
     }
 
     /**
      * Creates a Tailer for the given file, with a delay other than the default 1.0s.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param reOpen if true, close and reopen the file between reading chunks
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public Tailer(final File file, final TailerListener tailerListener, final long delayMillis, final boolean end, final boolean reOpen) {
         this(file, tailerListener, delayMillis, end, reOpen, IOUtils.DEFAULT_BUFFER_SIZE);
     }
 
     /**
      * Creates a Tailer for the given file, with a specified buffer size.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param reOpen if true, close and reopen the file between reading chunks
      * @param bufferSize Buffer size
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public Tailer(final File file, final TailerListener tailerListener, final long delayMillis, final boolean end, final boolean reOpen, final int bufferSize) {
         this(file, DEFAULT_CHARSET, tailerListener, delayMillis, end, reOpen, bufferSize);
     }
 
     /**
      * Creates a Tailer for the given file, with a specified buffer size.
      *
      * @param file the file to follow.
      * @param tailerListener the TailerListener to use.
      * @param delayMillis the delay between checks of the file for new content in milliseconds.
      * @param end Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param bufferSize Buffer size
      * @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}.
      */
     @Deprecated
     public Tailer(final File file, final TailerListener tailerListener, final long delayMillis, final boolean end, final int bufferSize) {
         this(file, tailerListener, delayMillis, end, false, bufferSize);
     }
 
     /**
      * Creates a Tailer for the given file, with a specified buffer size.
      *
      * @param tailable the file to follow.
      * @param charset the Charset to be used for reading the file
      * @param tailerListener the TailerListener to use.
      * @param delayDuration the delay between checks of the file for new content in milliseconds.
      * @param tailAtEnd Set to true to tail from the end of the file, false to tail from the beginning of the file.
      * @param reOpen if true, close and reopen the file between reading chunks
      * @param ignoreTouch if true, file timestamp changes without content change get ignored
      * @param bufferSize Buffer size
      */
     private Tailer(final Tailable tailable, final Charset charset, final TailerListener tailerListener, final Duration delayDuration, final boolean tailAtEnd,
             final boolean reOpen, final int bufferSize, final boolean ignoreTouch) {
         this.tailable = Objects.requireNonNull(tailable, "tailable");
         this.listener = Objects.requireNonNull(tailerListener, "listener");
         this.delayDuration = delayDuration;
         this.tailFromEnd = tailAtEnd;
         this.inbuf = IOUtils.byteArray(bufferSize);
         // Save and prepare the listener
         tailerListener.init(this);
         this.reOpen = reOpen;
         this.charset = charset;
         this.ignoreTouch = ignoreTouch;
     }
 
     /**
      * Requests the tailer to complete its current loop and return.
      */
     @Override
     public void close() {
         this.run = false;
     }
 
     /**
      * Gets the delay in milliseconds.
      *
      * @return the delay in milliseconds.
      * @deprecated Use {@link #getDelayDuration()}.
      */
     @Deprecated
     public long getDelay() {
         return delayDuration.toMillis();
     }
 
     /**
      * Gets the delay Duration.
      *
      * @return the delay Duration.
      * @since 2.12.0
      */
     public Duration getDelayDuration() {
         return delayDuration;
     }
 
     /**
      * Gets the file.
      *
      * @return the file
      * @throws IllegalStateException if constructed using a user provided {@link Tailable} implementation
      */
     public File getFile() {
         if (tailable instanceof TailablePath) {
             return ((TailablePath) tailable).getPath().toFile();
         }
         throw new IllegalStateException("Cannot extract java.io.File from " + tailable.getClass().getName());
     }
 
     /**
      * Gets whether to keep on running.
      *
      * @return whether to keep on running.
      * @since 2.5
      */
     protected boolean getRun() {
         return run;
     }
 
     /**
      * Gets the Tailable.
      *
      * @return the Tailable
      * @since 2.12.0
      */
     public Tailable getTailable() {
         return tailable;
     }
 
     /**
      * Reads new lines.
      *
      * @param reader The file to read
      * @return The new position after the lines have been read
      * @throws IOException if an I/O error occurs.
      */
     private long readLines(final RandomAccessResourceBridge reader) throws IOException {
         try (ByteArrayOutputStream lineBuf = new ByteArrayOutputStream(64)) {
             long pos = reader.getPointer();
             long rePos = pos; // position to re-read
             int num;
             boolean seenCR = false;
             while (getRun() && (num = reader.read(inbuf)) != EOF) {
                 for (int i = 0; i < num; i++) {
                     final byte ch = inbuf[i];
                     switch (ch) {
                     case LF:
                         seenCR = false; // swallow CR before LF
                         listener.handle(new String(lineBuf.toByteArray(), charset));
                         lineBuf.reset();
                         rePos = pos + i + 1;
                         break;
                     case CR:
                         if (seenCR) {
                             lineBuf.write(CR);
                         }
                         seenCR = true;
                         break;
                     default:
                         if (seenCR) {
                             seenCR = false; // swallow final CR
                             listener.handle(new String(lineBuf.toByteArray(), charset));
                             lineBuf.reset();
                             rePos = pos + i + 1;
                         }
                         lineBuf.write(ch);
                     }
                 }
                 pos = reader.getPointer();
             }
 
             reader.seek(rePos); // Ensure we can re-read if necessary
 
             if (listener instanceof TailerListenerAdapter) {
                 ((TailerListenerAdapter) listener).endOfFileReached();
             }
 
             return rePos;
         }
     }
 
     /**
      * Follows changes in the file, calling {@link TailerListener#handle(String)} with each new line.
      */
     @Override
     public void run() {
         RandomAccessResourceBridge reader = null;
         try {
             FileTime last = FileTimes.EPOCH; // The last time the file was checked for changes
             long position = 0; // position within the file
             // Open the file
             while (getRun() && reader == null) {
                 try {
                     reader = tailable.getRandomAccess(RAF_READ_ONLY_MODE);
                 } catch (final FileNotFoundException e) {
                     listener.fileNotFound();
                 }
                 if (reader == null) {
                     ThreadUtils.sleep(delayDuration);
                 } else {
                     // The current position in the file
                     position = tailFromEnd ? tailable.size() : 0;
                     last = tailable.lastModifiedFileTime();
                     reader.seek(position);
                 }
             }
             while (getRun()) {
                 final boolean newer = tailable.isNewer(last); // IO-279, must be done first
                 // Check the file length to see if it was rotated
                 final long length = tailable.size();
                 if (length < position) {
                     // File was rotated
                     listener.fileRotated();
                     // Reopen the reader after rotation ensuring that the old file is closed iff we re-open it
                     // successfully
                     try (RandomAccessResourceBridge save = reader) {
                         reader = tailable.getRandomAccess(RAF_READ_ONLY_MODE);
                         // At this point, we're sure that the old file is rotated
                         // Finish scanning the old file and then we'll start with the new one
                         try {
                             readLines(save);
                         } catch (final IOException ioe) {
                             listener.handle(ioe);
                         }
                         position = 0;
                     } catch (final FileNotFoundException e) {
                         // in this case we continue to use the previous reader and position values
                         listener.fileNotFound();
                         ThreadUtils.sleep(delayDuration);
                     }
                     continue;
                 }
                 // File was not rotated
                 // See if the file needs to be read again
                 if (length > position) {
                     // The file has more content than it did last time
                     position = readLines(reader);
                     last = tailable.lastModifiedFileTime();
                 } else if (newer) {
                     /*
                      * This can happen if the file
                      * - is overwritten with the exact same length of information
                      * - gets "touched"
                      * - Files.getLastModifiedTime returns a new timestamp but newer data is not yet there (
                      *   was reported to happen on busy systems or samba network shares, see IO-279)
                      * The default behaviour is to replay the whole file. If this is unsdesired in your usecase,
                      * use the ignoreTouch builder flag
                      */
                     if (!ignoreTouch) {
                         position = 0;
                         reader.seek(position); // cannot be null here
 
                         // Now we can read new lines
                         position = readLines(reader);
                     }
                     // we eitherway continue with the new timestamp
                     last = tailable.lastModifiedFileTime();
                 }
                 if (reOpen && reader != null) {
                     reader.close();
                 }
                 ThreadUtils.sleep(delayDuration);
                 if (getRun() && reOpen) {
                     reader = tailable.getRandomAccess(RAF_READ_ONLY_MODE);
                     reader.seek(position);
                 }
             }
         } catch (final InterruptedException e) {
             Thread.currentThread().interrupt();
             listener.handle(e);
         } catch (final Exception e) {
             listener.handle(e);
         } finally {
             try {
                 IOUtils.close(reader);
             } catch (final IOException e) {
                 listener.handle(e);
             }
             close();
         }
     }
 
     /**
      * Requests the tailer to complete its current loop and return.
      *
      * @deprecated Use {@link #close()}.
      */
     @Deprecated
     public void stop() {
         close();
     }
 }