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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package java.io;

import java.nio.charset.Charset;


Writes text to character files using a default buffer size. Encoding from characters to bytes uses either a specified charset or the platform's default charset. 
 Whether or not a file is available or may be created depends upon the underlying platform. Some platforms, in particular, allow a file to be opened for writing by only one FileWriter (or other file-writing object) at a time. In such situations the constructors in this class will fail if the file involved is already open. 
 The FileWriter is meant for writing streams of characters. For writing streams of raw bytes, consider using a FileOutputStream. 
Author:     Mark Reinhold
See Also:
Since:      1.1
/**
 * Writes text to character files using a default buffer size. Encoding from characters
 * to bytes uses either a specified {@linkplain java.nio.charset.Charset charset}
 * or the platform's
 * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}.
 *
 * <p>
 * Whether or not a file is available or may be created depends upon the
 * underlying platform.  Some platforms, in particular, allow a file to be
 * opened for writing by only one {@code FileWriter} (or other file-writing
 * object) at a time.  In such situations the constructors in this class
 * will fail if the file involved is already open.
 *
 * <p>
 * The {@code FileWriter} is meant for writing streams of characters. For writing
 * streams of raw bytes, consider using a {@code FileOutputStream}.
 *
 * @see OutputStreamWriter
 * @see FileOutputStream
 *
 * @author      Mark Reinhold
 * @since       1.1
 */

public class FileWriter extends OutputStreamWriter {

    
Constructs a FileWriter given a file name, using the platform's default charset 
Params:
  • fileName –  String The system-dependent filename.
Throws:
  • IOException –  if the named file exists but is a directory rather
                 than a regular file, does not exist but cannot be
                 created, or cannot be opened for any other reason
/**
     * Constructs a {@code FileWriter} given a file name, using the platform's
     * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}
     *
     * @param fileName  String The system-dependent filename.
     * @throws IOException  if the named file exists but is a directory rather
     *                  than a regular file, does not exist but cannot be
     *                  created, or cannot be opened for any other reason
     */
    public FileWriter(String fileName) throws IOException {
        super(new FileOutputStream(fileName));
    }

    
Constructs a FileWriter given a file name and a boolean indicating whether to append the data written, using the platform's default charset. 
Params:
  • fileName –  String The system-dependent filename.
  • append –  boolean if true, then data will be written to the end of the file rather than the beginning.
Throws:
  • IOException –  if the named file exists but is a directory rather
                 than a regular file, does not exist but cannot be
                 created, or cannot be opened for any other reason
/**
     * Constructs a {@code FileWriter} given a file name and a boolean indicating
     * whether to append the data written, using the platform's
     * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}.
     *
     * @param fileName  String The system-dependent filename.
     * @param append    boolean if {@code true}, then data will be written
     *                  to the end of the file rather than the beginning.
     * @throws IOException  if the named file exists but is a directory rather
     *                  than a regular file, does not exist but cannot be
     *                  created, or cannot be opened for any other reason
     */
    public FileWriter(String fileName, boolean append) throws IOException {
        super(new FileOutputStream(fileName, append));
    }

    
Constructs a FileWriter given the File to write, using the platform's default charset 
Params:
  • file –  the File to write.
Throws:
  • IOException –  if the file exists but is a directory rather than
                 a regular file, does not exist but cannot be created,
                 or cannot be opened for any other reason
/**
     * Constructs a {@code FileWriter} given the {@code File} to write,
     * using the platform's
     * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}
     *
     * @param file  the {@code File} to write.
     * @throws IOException  if the file exists but is a directory rather than
     *                  a regular file, does not exist but cannot be created,
     *                  or cannot be opened for any other reason
     */
    public FileWriter(File file) throws IOException {
        super(new FileOutputStream(file));
    }

    
Constructs a FileWriter given the File to write and a boolean indicating whether to append the data written, using the platform's default charset. 
Params:
  • file –  the File to write
  • append –  if true, then bytes will be written to the end of the file rather than the beginning
Throws:
  • IOException –  if the file exists but is a directory rather than
                 a regular file, does not exist but cannot be created,
                 or cannot be opened for any other reason
Since:1.4
/**
     * Constructs a {@code FileWriter} given the {@code File} to write and
     * a boolean indicating whether to append the data written, using the platform's
     * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}.
     *
     * @param file  the {@code File} to write
     * @param     append    if {@code true}, then bytes will be written
     *                      to the end of the file rather than the beginning
     * @throws IOException  if the file exists but is a directory rather than
     *                  a regular file, does not exist but cannot be created,
     *                  or cannot be opened for any other reason
     * @since 1.4
     */
    public FileWriter(File file, boolean append) throws IOException {
        super(new FileOutputStream(file, append));
    }

    
Constructs a FileWriter given a file descriptor, using the platform's default charset. 
Params:
  • fd –  the FileDescriptor to write.
/**
     * Constructs a {@code FileWriter} given a file descriptor,
     * using the platform's
     * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}.
     *
     * @param fd  the {@code FileDescriptor} to write.
     */
    public FileWriter(FileDescriptor fd) {
        super(new FileOutputStream(fd));
    }


    
Constructs a FileWriter given a file name and charset. 
Params:
  • fileName –  the name of the file to write
  • charset – the charset
Throws:
  • IOException –  if the named file exists but is a directory rather
                 than a regular file, does not exist but cannot be
                 created, or cannot be opened for any other reason
Since:11
/**
     * Constructs a {@code FileWriter} given a file name and
     * {@linkplain java.nio.charset.Charset charset}.
     *
     * @param fileName  the name of the file to write
     * @param charset the {@linkplain java.nio.charset.Charset charset}
     * @throws IOException  if the named file exists but is a directory rather
     *                  than a regular file, does not exist but cannot be
     *                  created, or cannot be opened for any other reason
     *
     * @since 11
     */
    public FileWriter(String fileName, Charset charset) throws IOException {
        super(new FileOutputStream(fileName), charset);
    }

    
Constructs a FileWriter given a file name, charset and a boolean indicating whether to append the data written. 
Params:
  • fileName –  the name of the file to write
  • charset – the charset
  • append –  a boolean. If true, the writer will write the data to the end of the file rather than the beginning.
Throws:
  • IOException –  if the named file exists but is a directory rather
                 than a regular file, does not exist but cannot be
                 created, or cannot be opened for any other reason
Since:11
/**
     * Constructs a {@code FileWriter} given a file name,
     * {@linkplain java.nio.charset.Charset charset} and a boolean indicating
     * whether to append the data written.
     *
     * @param fileName  the name of the file to write
     * @param charset the {@linkplain java.nio.charset.Charset charset}
     * @param append    a boolean. If {@code true}, the writer will write the data
     *                  to the end of the file rather than the beginning.
     * @throws IOException  if the named file exists but is a directory rather
     *                  than a regular file, does not exist but cannot be
     *                  created, or cannot be opened for any other reason
     *
     * @since 11
     */
    public FileWriter(String fileName, Charset charset, boolean append) throws IOException {
        super(new FileOutputStream(fileName, append), charset);
    }

    
Constructs a FileWriter given the File to write and charset. 
Params:
  • file –  the File to write
  • charset – the charset
Throws:
  • IOException –  if the file exists but is a directory rather than
                 a regular file, does not exist but cannot be created,
                 or cannot be opened for any other reason
Since:11
/**
     * Constructs a {@code FileWriter} given the {@code File} to write and
     * {@linkplain java.nio.charset.Charset charset}.
     *
     * @param file  the {@code File} to write
     * @param charset the {@linkplain java.nio.charset.Charset charset}
     * @throws IOException  if the file exists but is a directory rather than
     *                  a regular file, does not exist but cannot be created,
     *                  or cannot be opened for any other reason
     *
     * @since 11
     */
    public FileWriter(File file, Charset charset) throws IOException {
        super(new FileOutputStream(file), charset);
    }

    
Constructs a FileWriter given the File to write, charset and a boolean indicating whether to append the data written. 
Params:
  • file –  the File to write
  • charset – the charset
  • append –  a boolean. If true, the writer will write the data to the end of the file rather than the beginning.
Throws:
  • IOException –  if the file exists but is a directory rather than
                 a regular file, does not exist but cannot be created,
                 or cannot be opened for any other reason
Since:11
/**
     * Constructs a {@code FileWriter} given the {@code File} to write,
     * {@linkplain java.nio.charset.Charset charset} and a boolean indicating
     * whether to append the data written.
     *
     * @param file  the {@code File} to write
     * @param charset the {@linkplain java.nio.charset.Charset charset}
     * @param append    a boolean. If {@code true}, the writer will write the data
     *                  to the end of the file rather than the beginning.
     * @throws IOException  if the file exists but is a directory rather than
     *                  a regular file, does not exist but cannot be created,
     *                  or cannot be opened for any other reason
     * @since 11
     */
    public FileWriter(File file, Charset charset, boolean append) throws IOException {
        super(new FileOutputStream(file, append), charset);
    }
}