All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.apache.commons.io.output.FileWriterWithEncoding Maven / Gradle / Ivy

There is a newer version: 2.0.10
Show newest version
/*
 * 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.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import java.util.Objects;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;

/**
 * Writer of files that allows the encoding to be set.
 * 

* This class provides a simple alternative to FileWriter * that allows an encoding to be set. Unfortunately, it cannot subclass * FileWriter. *

* By default, the file will be overwritten, but this may be changed to append. *

* 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. *

* * * @since 1.4 * */ public class FileWriterWithEncoding extends Writer { // Cannot extend ProxyWriter, as requires writer to be // known when super() is called /** The writer to decorate. */ private final Writer out; /** * 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 */ 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 */ public FileWriterWithEncoding(final String fileName, final String charsetName, final boolean append) throws IOException { this(new File(fileName), charsetName, append); } /** * 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 */ 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 */ 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 */ 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 */ 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 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 */ 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, not null * @param append true if content should be appended, false to overwrite * @throws NullPointerException if the file or encoding is null * @throws IOException in case of an I/O error */ public FileWriterWithEncoding(final File file, final String charsetName, final boolean append) throws IOException { super(); this.out = initWriter(file, charsetName, append); } /** * 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 */ 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, not null * @param append true if content should be appended, false to overwrite * @throws NullPointerException if the file or encoding is null * @throws IOException in case of an I/O error */ public FileWriterWithEncoding(final File file, final Charset encoding, final boolean append) throws IOException { super(); this.out = 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 */ 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, not null * @param append true if content should be appended, false to overwrite * @throws NullPointerException if the file or encoding is null * @throws IOException in case of an I/O error */ public FileWriterWithEncoding(final File file, final CharsetEncoder charsetEncoder, final boolean append) throws IOException { super(); this.out = initWriter(file, charsetEncoder, append); } //----------------------------------------------------------------------- /** * Initialise 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 * @param append true to append * @return the initialized writer * @throws NullPointerException if the file or encoding is null * @throws IOException if an error occurs */ private static Writer initWriter(final File file, final Object encoding, final boolean append) throws IOException { Objects.requireNonNull(file, "file"); Objects.requireNonNull(encoding, "encoding"); OutputStream stream = null; final boolean fileExistedAlready = file.exists(); try { stream = new FileOutputStream(file, append); if (encoding instanceof Charset) { return new OutputStreamWriter(stream, (Charset)encoding); } else if (encoding instanceof CharsetEncoder) { return new OutputStreamWriter(stream, (CharsetEncoder)encoding); } else { return new OutputStreamWriter(stream, (String)encoding); } } catch (final IOException | RuntimeException ex) { try { IOUtils.close(stream); } catch (final IOException e) { ex.addSuppressed(e); } if (fileExistedAlready == false) { FileUtils.deleteQuietly(file); } throw ex; } } //----------------------------------------------------------------------- /** * Write a character. * @param idx the character to write * @throws IOException if an I/O error occurs */ @Override public void write(final int idx) throws IOException { out.write(idx); } /** * Write the characters from an array. * @param chr the characters to write * @throws IOException if an I/O error occurs */ @Override public void write(final char[] chr) throws IOException { out.write(chr); } /** * Write the specified characters from an array. * @param chr the characters to write * @param st The start offset * @param end The number of characters to write * @throws IOException if an I/O error occurs */ @Override public void write(final char[] chr, final int st, final int end) throws IOException { out.write(chr, st, end); } /** * Write the characters from a string. * @param str the string to write * @throws IOException if an I/O error occurs */ @Override public void write(final String str) throws IOException { out.write(str); } /** * Write the specified characters from a string. * @param str the string to write * @param st The start offset * @param end The number of characters to write * @throws IOException if an I/O error occurs */ @Override public void write(final String str, final int st, final int end) throws IOException { out.write(str, st, end); } /** * Flush the stream. * @throws IOException if an I/O error occurs */ @Override public void flush() throws IOException { out.flush(); } /** * Close the stream. * @throws IOException if an I/O error occurs */ @Override public void close() throws IOException { out.close(); } }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy