FileWriterWithEncoding.java
/*
* 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.output;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import java.util.Objects;
import org.apache.commons.io.Charsets;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.io.build.AbstractOrigin;
import org.apache.commons.io.build.AbstractStreamBuilder;
/**
* Writer of files that allows the encoding to be set.
* <p>
* This class provides a simple alternative to {@link FileWriter} that allows an encoding to be set. Unfortunately, it cannot subclass {@link FileWriter}.
* </p>
* <p>
* By default, the file will be overwritten, but this may be changed to append.
* </p>
* <p>
* The encoding must be specified using either the name of the {@link Charset}, the {@link Charset}, or a {@link CharsetEncoder}. If the default encoding is
* required then use the {@link java.io.FileWriter} directly, rather than this implementation.
* </p>
* <p>
* To build an instance, use {@link Builder}.
* </p>
*
* @see Builder
* @since 1.4
*/
public class FileWriterWithEncoding extends ProxyWriter {
// @formatter:off
/**
* Builds a new {@link FileWriterWithEncoding}.
*
* <p>
* Using a CharsetEncoder:
* </p>
* <pre>{@code
* FileWriterWithEncoding w = FileWriterWithEncoding.builder()
* .setPath(path)
* .setAppend(false)
* .setCharsetEncoder(StandardCharsets.UTF_8.newEncoder())
* .get();}
* </pre>
* <p>
* Using a Charset:
* </p>
* <pre>{@code
* FileWriterWithEncoding w = FileWriterWithEncoding.builder()
* .setPath(path)
* .setAppend(false)
* .setCharsetEncoder(StandardCharsets.UTF_8)
* .get();}
* </pre>
*
* @see #get()
* @since 2.12.0
*/
// @formatter:on
public static class Builder extends AbstractStreamBuilder<FileWriterWithEncoding, Builder> {
private boolean append;
private CharsetEncoder charsetEncoder = super.getCharset().newEncoder();
/**
* Builds a new {@link FileWriterWithEncoding}.
* <p>
* You must set input that supports {@link File} on this builder, otherwise, this method throws an exception.
* </p>
* <p>
* This builder use the following aspects:
* </p>
* <ul>
* <li>{@link File}</li>
* <li>{@link CharsetEncoder}</li>
* <li>append</li>
* </ul>
*
* @return a new instance.
* @throws UnsupportedOperationException if the origin cannot provide a File.
* @throws IllegalStateException if the {@code origin} is {@code null}.
* @see AbstractOrigin#getFile()
*/
@SuppressWarnings("resource")
@Override
public FileWriterWithEncoding get() throws IOException {
if (charsetEncoder != null && getCharset() != null && !charsetEncoder.charset().equals(getCharset())) {
throw new IllegalStateException(String.format("Mismatched Charset(%s) and CharsetEncoder(%s)", getCharset(), charsetEncoder.charset()));
}
final Object encoder = charsetEncoder != null ? charsetEncoder : getCharset();
return new FileWriterWithEncoding(FileWriterWithEncoding.initWriter(checkOrigin().getFile(), encoder, append));
}
/**
* Sets whether or not to append.
*
* @param append Whether or not to append.
* @return this
*/
public Builder setAppend(final boolean append) {
this.append = append;
return this;
}
/**
* Sets charsetEncoder to use for encoding.
*
* @param charsetEncoder The charsetEncoder to use for encoding.
* @return this
*/
public Builder setCharsetEncoder(final CharsetEncoder charsetEncoder) {
this.charsetEncoder = charsetEncoder;
return this;
}
}
/**
* Constructs a new {@link Builder}.
*
* @return Creates a new {@link Builder}.
* @since 2.12.0
*/
public static Builder builder() {
return new Builder();
}
/**
* Initializes the wrapped file writer. Ensure that a cleanup occurs if the writer creation fails.
*
* @param file the file to be accessed
* @param encoding the encoding to use - may be Charset, CharsetEncoder or String, null uses the default Charset.
* @param append true to append
* @return a new initialized OutputStreamWriter
* @throws IOException if an error occurs
*/
private static OutputStreamWriter initWriter(final File file, final Object encoding, final boolean append) throws IOException {
Objects.requireNonNull(file, "file");
OutputStream outputStream = null;
final boolean fileExistedAlready = file.exists();
try {
outputStream = FileUtils.newOutputStream(file, append);
if (encoding == null || encoding instanceof Charset) {
return new OutputStreamWriter(outputStream, Charsets.toCharset((Charset) encoding));
}
if (encoding instanceof CharsetEncoder) {
return new OutputStreamWriter(outputStream, (CharsetEncoder) encoding);
}
return new OutputStreamWriter(outputStream, (String) encoding);
} catch (final IOException | RuntimeException ex) {
try {
IOUtils.close(outputStream);
} catch (final IOException e) {
ex.addSuppressed(e);
}
if (!fileExistedAlready) {
FileUtils.deleteQuietly(file);
}
throw ex;
}
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param file the file to write to, not null
* @param charset the encoding to use, not null
* @throws NullPointerException if the file or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final File file, final Charset charset) throws IOException {
this(file, charset, false);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param file the file to write to, not null.
* @param encoding the name of the requested charset, null uses the default Charset.
* @param append true if content should be appended, false to overwrite.
* @throws NullPointerException if the file is null.
* @throws IOException in case of an I/O error.
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
@SuppressWarnings("resource") // Call site is responsible for closing a new instance.
public FileWriterWithEncoding(final File file, final Charset encoding, final boolean append) throws IOException {
this(initWriter(file, encoding, append));
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param file the file to write to, not null
* @param charsetEncoder the encoding to use, not null
* @throws NullPointerException if the file or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final File file, final CharsetEncoder charsetEncoder) throws IOException {
this(file, charsetEncoder, false);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param file the file to write to, not null.
* @param charsetEncoder the encoding to use, null uses the default Charset.
* @param append true if content should be appended, false to overwrite.
* @throws NullPointerException if the file is null.
* @throws IOException in case of an I/O error.
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
@SuppressWarnings("resource") // Call site is responsible for closing a new instance.
public FileWriterWithEncoding(final File file, final CharsetEncoder charsetEncoder, final boolean append) throws IOException {
this(initWriter(file, charsetEncoder, append));
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param file the file to write to, not null
* @param charsetName the name of the requested charset, not null
* @throws NullPointerException if the file or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final File file, final String charsetName) throws IOException {
this(file, charsetName, false);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param file the file to write to, not null.
* @param charsetName the name of the requested charset, null uses the default Charset.
* @param append true if content should be appended, false to overwrite.
* @throws NullPointerException if the file is null.
* @throws IOException in case of an I/O error.
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
@SuppressWarnings("resource") // Call site is responsible for closing a new instance.
public FileWriterWithEncoding(final File file, final String charsetName, final boolean append) throws IOException {
this(initWriter(file, charsetName, append));
}
private FileWriterWithEncoding(final OutputStreamWriter outputStreamWriter) {
super(outputStreamWriter);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param fileName the name of the file to write to, not null
* @param charset the charset to use, not null
* @throws NullPointerException if the file name or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final String fileName, final Charset charset) throws IOException {
this(new File(fileName), charset, false);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param fileName the name of the file to write to, not null
* @param charset the encoding to use, not null
* @param append true if content should be appended, false to overwrite
* @throws NullPointerException if the file name or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final String fileName, final Charset charset, final boolean append) throws IOException {
this(new File(fileName), charset, append);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param fileName the name of the file to write to, not null
* @param encoding the encoding to use, not null
* @throws NullPointerException if the file name or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final String fileName, final CharsetEncoder encoding) throws IOException {
this(new File(fileName), encoding, false);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param fileName the name of the file to write to, not null
* @param charsetEncoder the encoding to use, not null
* @param append true if content should be appended, false to overwrite
* @throws NullPointerException if the file name or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final String fileName, final CharsetEncoder charsetEncoder, final boolean append) throws IOException {
this(new File(fileName), charsetEncoder, append);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param fileName the name of the file to write to, not null
* @param charsetName the name of the requested charset, not null
* @throws NullPointerException if the file name or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final String fileName, final String charsetName) throws IOException {
this(new File(fileName), charsetName, false);
}
/**
* Constructs a FileWriterWithEncoding with a file encoding.
*
* @param fileName the name of the file to write to, not null
* @param charsetName the name of the requested charset, not null
* @param append true if content should be appended, false to overwrite
* @throws NullPointerException if the file name or encoding is null
* @throws IOException in case of an I/O error
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public FileWriterWithEncoding(final String fileName, final String charsetName, final boolean append) throws IOException {
this(new File(fileName), charsetName, append);
}
}