ojluni/src/main/java/java/io/FileOutputStream.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 1994, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * 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).
  *
  * You should have received a copy of the GNU General Public License version
  * 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
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 package java.io;

 import java.nio.channels.FileChannel;
 import sun.nio.ch.FileChannelImpl;
 import sun.misc.IoTrace;


 /**
  * A file output stream is an output stream for writing data to a
  * <code>File</code> or to a <code>FileDescriptor</code>. 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 <tt>FileOutputStream</tt> (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><code>FileOutputStream</code> is meant for writing streams of raw bytes
  * such as image data. For writing streams of characters, consider using
  * <code>FileWriter</code>.
  *
  * @author  Arthur van Hoff
  * @see     java.io.File
  * @see     java.io.FileDescriptor
  * @see     java.io.FileInputStream
  * @see     java.nio.file.Files#newOutputStream
  * @since   JDK1.0
  */
 public
 class FileOutputStream extends OutputStream
 {
     /**
      * The system dependent file descriptor.
      */
     private final FileDescriptor fd;

     /**
      * The path of the referenced file (null if the stream is created with a file descriptor)
      */
     private final String path;

     /**
      * True if the file is opened for append.
      */
     private final boolean append;

     /**
      * The associated channel, initalized lazily.
      */
     private FileChannel channel;

     private final Object closeLock = new Object();
     private volatile boolean closed = false;
     private static final ThreadLocal<Boolean> runningFinalize =
         new ThreadLocal<>();

     private static boolean isRunningFinalize() {
         Boolean val;
         if ((val = runningFinalize.get()) != null)
             return val.booleanValue();
         return false;
     }

     /**
      * Creates a file output stream to write to the file with the
      * specified name. A new <code>FileDescriptor</code> object is
      * created to represent this file connection.
      * <p>
      * First, if there is a security manager, its <code>checkWrite</code>
      * method is called with <code>name</code> as its argument.
      * <p>
      * 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 then a <code>FileNotFoundException</code> is thrown.
      *
      * @param      name   the system-dependent filename
      * @exception  FileNotFoundException  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
      * @exception  SecurityException  if a security manager exists and its
      *               <code>checkWrite</code> method denies write access
      *               to the file.
      * @see        java.lang.SecurityManager#checkWrite(java.lang.String)
      */
     public FileOutputStream(String name) throws FileNotFoundException {
         this(name != null ? new File(name) : null, false);
     }

     /**
      * Creates a file output stream to write to the file with the specified
      * name.  If the second argument is <code>true</code>, then
      * bytes will be written to the end of the file rather than the beginning.
      * A new <code>FileDescriptor</code> object is created to represent this
      * file connection.
      * <p>
      * First, if there is a security manager, its <code>checkWrite</code>
      * method is called with <code>name</code> as its argument.
      * <p>
      * 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 then a <code>FileNotFoundException</code> is thrown.
      *
      * @param     name        the system-dependent file name
      * @param     append      if <code>true</code>, then bytes will be written
      *                   to the end of the file rather than the beginning
      * @exception  FileNotFoundException  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.
      * @exception  SecurityException  if a security manager exists and its
      *               <code>checkWrite</code> method denies write access
      *               to the file.
      * @see        java.lang.SecurityManager#checkWrite(java.lang.String)
      * @since     JDK1.1
      */
     public FileOutputStream(String name, boolean append)
         throws FileNotFoundException
     {
         this(name != null ? new File(name) : null, append);
     }

     /**
      * Creates a file output stream to write to the file represented by
      * the specified <code>File</code> object. A new
      * <code>FileDescriptor</code> object is created to represent this
      * file connection.
      * <p>
      * First, if there is a security manager, its <code>checkWrite</code>
      * method is called with the path represented by the <code>file</code>
      * argument as its argument.
      * <p>
      * 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 then a <code>FileNotFoundException</code> is thrown.
      *
      * @param      file               the file to be opened for writing.
      * @exception  FileNotFoundException  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
      * @exception  SecurityException  if a security manager exists and its
      *               <code>checkWrite</code> method denies write access
      *               to the file.
      * @see        java.io.File#getPath()
      * @see        java.lang.SecurityException
      * @see        java.lang.SecurityManager#checkWrite(java.lang.String)
      */
     public FileOutputStream(File file) throws FileNotFoundException {
         this(file, false);
     }

     /**
      * Creates a file output stream to write to the file represented by
      * the specified <code>File</code> object. If the second argument is
      * <code>true</code>, then bytes will be written to the end of the file
      * rather than the beginning. A new <code>FileDescriptor</code> object is
      * created to represent this file connection.
      * <p>
      * First, if there is a security manager, its <code>checkWrite</code>
      * method is called with the path represented by the <code>file</code>
      * argument as its argument.
      * <p>
      * 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 then a <code>FileNotFoundException</code> is thrown.
      *
      * @param      file               the file to be opened for writing.
      * @param     append      if <code>true</code>, then bytes will be written
      *                   to the end of the file rather than the beginning
      * @exception  FileNotFoundException  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
      * @exception  SecurityException  if a security manager exists and its
      *               <code>checkWrite</code> method denies write access
      *               to the file.
      * @see        java.io.File#getPath()
      * @see        java.lang.SecurityException
      * @see        java.lang.SecurityManager#checkWrite(java.lang.String)
      * @since 1.4
      */
     public FileOutputStream(File file, boolean append)
         throws FileNotFoundException
     {
         String name = (file != null ? file.getPath() : null);
         SecurityManager security = System.getSecurityManager();
         if (security != null) {
             security.checkWrite(name);
         }
         if (name == null) {
             throw new NullPointerException();
         }
         if (file.isInvalid()) {
             throw new FileNotFoundException("Invalid file path");
         }
         this.fd = new FileDescriptor();
         this.append = append;
         this.path = name;
         fd.incrementAndGetUseCount();
         open(name, append);
     }

     /**
      * Creates a file output stream to write to the specified file
      * descriptor, which represents an existing connection to an actual
      * file in the file system.
      * <p>
      * First, if there is a security manager, its <code>checkWrite</code>
      * method is called with the file descriptor <code>fdObj</code>
      * argument as its argument.
      * <p>
      * If <code>fdObj</code> is null then a <code>NullPointerException</code>
      * is thrown.
      * <p>
      * This constructor does not throw an exception if <code>fdObj</code>
      * is {@link java.io.FileDescriptor#valid() invalid}.
      * However, if the methods are invoked on the resulting stream to attempt
      * I/O on the stream, an <code>IOException</code> is thrown.
      *
      * @param      fdObj   the file descriptor to be opened for writing
      * @exception  SecurityException  if a security manager exists and its
      *               <code>checkWrite</code> method denies
      *               write access to the file descriptor
      * @see        java.lang.SecurityManager#checkWrite(java.io.FileDescriptor)
      */
     public FileOutputStream(FileDescriptor fdObj) {
         SecurityManager security = System.getSecurityManager();
         if (fdObj == null) {
             throw new NullPointerException();
         }
         if (security != null) {
             security.checkWrite(fdObj);
         }
         this.fd = fdObj;
         this.path = null;
         this.append = false;

         /*
          * FileDescriptor is being shared by streams.
          * Ensure that it's GC'ed only when all the streams/channels are done
          * using it.
          */
         fd.incrementAndGetUseCount();
     }

     /**
      * Opens a file, with the specified name, for overwriting or appending.
      * @param name name of file to be opened
      * @param append whether the file is to be opened in append mode
      */
     private native void open(String name, boolean append)
         throws FileNotFoundException;

     /**
      * Writes the specified byte to this file output stream.
      *
      * @param   b   the byte to be written.
      * @param   append   {@code true} if the write operation first
      *     advances the position to the end of file
      */
     private native void write(int b, boolean append) throws IOException;

     /**
      * Writes the specified byte to this file output stream. Implements
      * the <code>write</code> method of <code>OutputStream</code>.
      *
      * @param      b   the byte to be written.
      * @exception  IOException  if an I/O error occurs.
      */
     public void write(int b) throws IOException {
         Object traceContext = IoTrace.fileWriteBegin(path);
         int bytesWritten = 0;
         try {
             write(b, append);
             bytesWritten = 1;
         } finally {
             IoTrace.fileWriteEnd(traceContext, bytesWritten);
         }
     }

     /**
      * Writes a sub array as a sequence of bytes.
      * @param b the data to be written
      * @param off the start offset in the data
      * @param len the number of bytes that are written
      * @param append {@code true} to first advance the position to the
      *     end of file
      * @exception IOException If an I/O error has occurred.
      */
     private native void writeBytes(byte b[], int off, int len, boolean append)
         throws IOException;

     /**
      * Writes <code>b.length</code> bytes from the specified byte array
      * to this file output stream.
      *
      * @param      b   the data.
      * @exception  IOException  if an I/O error occurs.
      */
     public void write(byte b[]) throws IOException {
         Object traceContext = IoTrace.fileWriteBegin(path);
         int bytesWritten = 0;
         try {
             writeBytes(b, 0, b.length, append);
             bytesWritten = b.length;
         } finally {
             IoTrace.fileWriteEnd(traceContext, bytesWritten);
         }
     }

     /**
      * Writes <code>len</code> bytes from the specified byte array
      * starting at offset <code>off</code> to this file output stream.
      *
      * @param      b     the data.
      * @param      off   the start offset in the data.
      * @param      len   the number of bytes to write.
      * @exception  IOException  if an I/O error occurs.
      */
     public void write(byte b[], int off, int len) throws IOException {
         Object traceContext = IoTrace.fileWriteBegin(path);
         int bytesWritten = 0;
         try {
             writeBytes(b, off, len, append);
             bytesWritten = len;
         } finally {
             IoTrace.fileWriteEnd(traceContext, bytesWritten);
         }
     }

     /**
      * Closes this file output stream and releases any system resources
      * associated with this stream. This file output stream may no longer
      * be used for writing bytes.
      *
      * <p> If this stream has an associated channel then the channel is closed
      * as well.
      *
      * @exception  IOException  if an I/O error occurs.
      *
      * @revised 1.4
      * @spec JSR-51
      */
     public void close() throws IOException {
         synchronized (closeLock) {
             if (closed) {
                 return;
             }
             closed = true;
         }

         if (channel != null) {
             /*
              * Decrement FD use count associated with the channel
              * The use count is incremented whenever a new channel
              * is obtained from this stream.
              */
             fd.decrementAndGetUseCount();
             channel.close();
         }

         /*
          * Decrement FD use count associated with this stream
          */
         int useCount = fd.decrementAndGetUseCount();

         /*
          * If FileDescriptor is still in use by another stream, the finalizer
          * will not close it.
          */
         if ((useCount <= 0) || !isRunningFinalize()) {
             close0();
         }
     }

     /**
      * Returns the file descriptor associated with this stream.
      *
      * @return  the <code>FileDescriptor</code> object that represents
      *          the connection to the file in the file system being used
      *          by this <code>FileOutputStream</code> object.
      *
      * @exception  IOException  if an I/O error occurs.
      * @see        java.io.FileDescriptor
      */
      public final FileDescriptor getFD()  throws IOException {
         if (fd != null) return fd;
         throw new IOException();
      }

     /**
      * Returns the unique {@link java.nio.channels.FileChannel FileChannel}
      * object associated with this file output stream. </p>
      *
      * <p> The initial {@link java.nio.channels.FileChannel#position()
      * </code>position<code>} of the returned channel will be equal to the
      * number of bytes written to the file so far unless this stream is in
      * append mode, in which case it will be equal to the size of the file.
      * Writing bytes to this stream will increment the channel's position
      * accordingly.  Changing the channel's position, either explicitly or by
      * writing, will change this stream's file position.
      *
      * @return  the file channel associated with this file output stream
      *
      * @since 1.4
      * @spec JSR-51
      */
     public FileChannel getChannel() {
         synchronized (this) {
             if (channel == null) {
                 channel = FileChannelImpl.open(fd, path, false, true, append, this);

                 /*
                  * Increment fd's use count. Invoking the channel's close()
                  * method will result in decrementing the use count set for
                  * the channel.
                  */
                 fd.incrementAndGetUseCount();
             }
             return channel;
         }
     }

     /**
      * Cleans up the connection to the file, and ensures that the
      * <code>close</code> method of this file output stream is
      * called when there are no more references to this stream.
      *
      * @exception  IOException  if an I/O error occurs.
      * @see        java.io.FileInputStream#close()
      */
     protected void finalize() throws IOException {
         if (fd != null) {
             if (fd == FileDescriptor.out || fd == FileDescriptor.err) {
                 flush();
             } else {

                 /*
                  * Finalizer should not release the FileDescriptor if another
                  * stream is still using it. If the user directly invokes
                  * close() then the FileDescriptor is also released.
                  */
                 runningFinalize.set(Boolean.TRUE);
                 try {
                     close();
                 } finally {
                     runningFinalize.set(Boolean.FALSE);
                 }
             }
         }
     }

     private native void close0() throws IOException;

     private static native void initIDs();

     static {
         initIDs();
     }

 }
	/*
	* Copyright (c) 1994, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* 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).
	*
	* You should have received a copy of the GNU General Public License version
	* 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
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.io;

	import java.nio.channels.FileChannel;
	import sun.nio.ch.FileChannelImpl;
	import sun.misc.IoTrace;


	/**
	* A file output stream is an output stream for writing data to a
	* <code>File</code> or to a <code>FileDescriptor</code>. 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 <tt>FileOutputStream</tt> (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><code>FileOutputStream</code> is meant for writing streams of raw bytes
	* such as image data. For writing streams of characters, consider using
	* <code>FileWriter</code>.
	*
	* @author Arthur van Hoff
	* @see java.io.File
	* @see java.io.FileDescriptor
	* @see java.io.FileInputStream
	* @see java.nio.file.Files#newOutputStream
	* @since JDK1.0
	*/
	public
	class FileOutputStream extends OutputStream
	{
	/**
	* The system dependent file descriptor.
	*/
	private final FileDescriptor fd;

	/**
	* The path of the referenced file (null if the stream is created with a file descriptor)
	*/
	private final String path;

	/**
	* True if the file is opened for append.
	*/
	private final boolean append;

	/**
	* The associated channel, initalized lazily.
	*/
	private FileChannel channel;

	private final Object closeLock = new Object();
	private volatile boolean closed = false;
	private static final ThreadLocal<Boolean> runningFinalize =
	new ThreadLocal<>();

	private static boolean isRunningFinalize() {
	Boolean val;
	if ((val = runningFinalize.get()) != null)
	return val.booleanValue();
	return false;
	}

	/**
	* Creates a file output stream to write to the file with the
	* specified name. A new <code>FileDescriptor</code> object is
	* created to represent this file connection.
	* <p>
	* First, if there is a security manager, its <code>checkWrite</code>
	* method is called with <code>name</code> as its argument.
	* <p>
	* 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 then a <code>FileNotFoundException</code> is thrown.
	*
	* @param name the system-dependent filename
	* @exception FileNotFoundException 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
	* @exception SecurityException if a security manager exists and its
	* <code>checkWrite</code> method denies write access
	* to the file.
	* @see java.lang.SecurityManager#checkWrite(java.lang.String)
	*/
	public FileOutputStream(String name) throws FileNotFoundException {
	this(name != null ? new File(name) : null, false);
	}

	/**
	* Creates a file output stream to write to the file with the specified
	* name. If the second argument is <code>true</code>, then
	* bytes will be written to the end of the file rather than the beginning.
	* A new <code>FileDescriptor</code> object is created to represent this
	* file connection.
	* <p>
	* First, if there is a security manager, its <code>checkWrite</code>
	* method is called with <code>name</code> as its argument.
	* <p>
	* 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 then a <code>FileNotFoundException</code> is thrown.
	*
	* @param name the system-dependent file name
	* @param append if <code>true</code>, then bytes will be written
	* to the end of the file rather than the beginning
	* @exception FileNotFoundException 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.
	* @exception SecurityException if a security manager exists and its
	* <code>checkWrite</code> method denies write access
	* to the file.
	* @see java.lang.SecurityManager#checkWrite(java.lang.String)
	* @since JDK1.1
	*/
	public FileOutputStream(String name, boolean append)
	throws FileNotFoundException
	{
	this(name != null ? new File(name) : null, append);
	}

	/**
	* Creates a file output stream to write to the file represented by
	* the specified <code>File</code> object. A new
	* <code>FileDescriptor</code> object is created to represent this
	* file connection.
	* <p>
	* First, if there is a security manager, its <code>checkWrite</code>
	* method is called with the path represented by the <code>file</code>
	* argument as its argument.
	* <p>
	* 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 then a <code>FileNotFoundException</code> is thrown.
	*
	* @param file the file to be opened for writing.
	* @exception FileNotFoundException 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
	* @exception SecurityException if a security manager exists and its
	* <code>checkWrite</code> method denies write access
	* to the file.
	* @see java.io.File#getPath()
	* @see java.lang.SecurityException
	* @see java.lang.SecurityManager#checkWrite(java.lang.String)
	*/
	public FileOutputStream(File file) throws FileNotFoundException {
	this(file, false);
	}

	/**
	* Creates a file output stream to write to the file represented by
	* the specified <code>File</code> object. If the second argument is
	* <code>true</code>, then bytes will be written to the end of the file
	* rather than the beginning. A new <code>FileDescriptor</code> object is
	* created to represent this file connection.
	* <p>
	* First, if there is a security manager, its <code>checkWrite</code>
	* method is called with the path represented by the <code>file</code>
	* argument as its argument.
	* <p>
	* 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 then a <code>FileNotFoundException</code> is thrown.
	*
	* @param file the file to be opened for writing.
	* @param append if <code>true</code>, then bytes will be written
	* to the end of the file rather than the beginning
	* @exception FileNotFoundException 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
	* @exception SecurityException if a security manager exists and its
	* <code>checkWrite</code> method denies write access
	* to the file.
	* @see java.io.File#getPath()
	* @see java.lang.SecurityException
	* @see java.lang.SecurityManager#checkWrite(java.lang.String)
	* @since 1.4
	*/
	public FileOutputStream(File file, boolean append)
	throws FileNotFoundException
	{
	String name = (file != null ? file.getPath() : null);
	SecurityManager security = System.getSecurityManager();
	if (security != null) {
	security.checkWrite(name);
	}
	if (name == null) {
	throw new NullPointerException();
	}
	if (file.isInvalid()) {
	throw new FileNotFoundException("Invalid file path");
	}
	this.fd = new FileDescriptor();
	this.append = append;
	this.path = name;
	fd.incrementAndGetUseCount();
	open(name, append);
	}

	/**
	* Creates a file output stream to write to the specified file
	* descriptor, which represents an existing connection to an actual
	* file in the file system.
	* <p>
	* First, if there is a security manager, its <code>checkWrite</code>
	* method is called with the file descriptor <code>fdObj</code>
	* argument as its argument.
	* <p>
	* If <code>fdObj</code> is null then a <code>NullPointerException</code>
	* is thrown.
	* <p>
	* This constructor does not throw an exception if <code>fdObj</code>
	* is {@link java.io.FileDescriptor#valid() invalid}.
	* However, if the methods are invoked on the resulting stream to attempt
	* I/O on the stream, an <code>IOException</code> is thrown.
	*
	* @param fdObj the file descriptor to be opened for writing
	* @exception SecurityException if a security manager exists and its
	* <code>checkWrite</code> method denies
	* write access to the file descriptor
	* @see java.lang.SecurityManager#checkWrite(java.io.FileDescriptor)
	*/
	public FileOutputStream(FileDescriptor fdObj) {
	SecurityManager security = System.getSecurityManager();
	if (fdObj == null) {
	throw new NullPointerException();
	}
	if (security != null) {
	security.checkWrite(fdObj);
	}
	this.fd = fdObj;
	this.path = null;
	this.append = false;

	/*
	* FileDescriptor is being shared by streams.
	* Ensure that it's GC'ed only when all the streams/channels are done
	* using it.
	*/
	fd.incrementAndGetUseCount();
	}

	/**
	* Opens a file, with the specified name, for overwriting or appending.
	* @param name name of file to be opened
	* @param append whether the file is to be opened in append mode
	*/
	private native void open(String name, boolean append)
	throws FileNotFoundException;

	/**
	* Writes the specified byte to this file output stream.
	*
	* @param b the byte to be written.
	* @param append {@code true} if the write operation first
	* advances the position to the end of file
	*/
	private native void write(int b, boolean append) throws IOException;

	/**
	* Writes the specified byte to this file output stream. Implements
	* the <code>write</code> method of <code>OutputStream</code>.
	*
	* @param b the byte to be written.
	* @exception IOException if an I/O error occurs.
	*/
	public void write(int b) throws IOException {
	Object traceContext = IoTrace.fileWriteBegin(path);
	int bytesWritten = 0;
	try {
	write(b, append);
	bytesWritten = 1;
	} finally {
	IoTrace.fileWriteEnd(traceContext, bytesWritten);
	}
	}

	/**
	* Writes a sub array as a sequence of bytes.
	* @param b the data to be written
	* @param off the start offset in the data
	* @param len the number of bytes that are written
	* @param append {@code true} to first advance the position to the
	* end of file
	* @exception IOException If an I/O error has occurred.
	*/
	private native void writeBytes(byte b[], int off, int len, boolean append)
	throws IOException;

	/**
	* Writes <code>b.length</code> bytes from the specified byte array
	* to this file output stream.
	*
	* @param b the data.
	* @exception IOException if an I/O error occurs.
	*/
	public void write(byte b[]) throws IOException {
	Object traceContext = IoTrace.fileWriteBegin(path);
	int bytesWritten = 0;
	try {
	writeBytes(b, 0, b.length, append);
	bytesWritten = b.length;
	} finally {
	IoTrace.fileWriteEnd(traceContext, bytesWritten);
	}
	}

	/**
	* Writes <code>len</code> bytes from the specified byte array
	* starting at offset <code>off</code> to this file output stream.
	*
	* @param b the data.
	* @param off the start offset in the data.
	* @param len the number of bytes to write.
	* @exception IOException if an I/O error occurs.
	*/
	public void write(byte b[], int off, int len) throws IOException {
	Object traceContext = IoTrace.fileWriteBegin(path);
	int bytesWritten = 0;
	try {
	writeBytes(b, off, len, append);
	bytesWritten = len;
	} finally {
	IoTrace.fileWriteEnd(traceContext, bytesWritten);
	}
	}

	/**
	* Closes this file output stream and releases any system resources
	* associated with this stream. This file output stream may no longer
	* be used for writing bytes.
	*
	* <p> If this stream has an associated channel then the channel is closed
	* as well.
	*
	* @exception IOException if an I/O error occurs.
	*
	* @revised 1.4
	* @spec JSR-51
	*/
	public void close() throws IOException {
	synchronized (closeLock) {
	if (closed) {
	return;
	}
	closed = true;
	}

	if (channel != null) {
	/*
	* Decrement FD use count associated with the channel
	* The use count is incremented whenever a new channel
	* is obtained from this stream.
	*/
	fd.decrementAndGetUseCount();
	channel.close();
	}

	/*
	* Decrement FD use count associated with this stream
	*/
	int useCount = fd.decrementAndGetUseCount();

	/*
	* If FileDescriptor is still in use by another stream, the finalizer
	* will not close it.
	*/
	if ((useCount <= 0) \|\| !isRunningFinalize()) {
	close0();
	}
	}

	/**
	* Returns the file descriptor associated with this stream.
	*
	* @return the <code>FileDescriptor</code> object that represents
	* the connection to the file in the file system being used
	* by this <code>FileOutputStream</code> object.
	*
	* @exception IOException if an I/O error occurs.
	* @see java.io.FileDescriptor
	*/
	public final FileDescriptor getFD() throws IOException {
	if (fd != null) return fd;
	throw new IOException();
	}

	/**
	* Returns the unique {@link java.nio.channels.FileChannel FileChannel}
	* object associated with this file output stream. </p>
	*
	* <p> The initial {@link java.nio.channels.FileChannel#position()
	* </code>position<code>} of the returned channel will be equal to the
	* number of bytes written to the file so far unless this stream is in
	* append mode, in which case it will be equal to the size of the file.
	* Writing bytes to this stream will increment the channel's position
	* accordingly. Changing the channel's position, either explicitly or by
	* writing, will change this stream's file position.
	*
	* @return the file channel associated with this file output stream
	*
	* @since 1.4
	* @spec JSR-51
	*/
	public FileChannel getChannel() {
	synchronized (this) {
	if (channel == null) {
	channel = FileChannelImpl.open(fd, path, false, true, append, this);

	/*
	* Increment fd's use count. Invoking the channel's close()
	* method will result in decrementing the use count set for
	* the channel.
	*/
	fd.incrementAndGetUseCount();
	}
	return channel;
	}
	}

	/**
	* Cleans up the connection to the file, and ensures that the
	* <code>close</code> method of this file output stream is
	* called when there are no more references to this stream.
	*
	* @exception IOException if an I/O error occurs.
	* @see java.io.FileInputStream#close()
	*/
	protected void finalize() throws IOException {
	if (fd != null) {
	if (fd == FileDescriptor.out \|\| fd == FileDescriptor.err) {
	flush();
	} else {

	/*
	* Finalizer should not release the FileDescriptor if another
	* stream is still using it. If the user directly invokes
	* close() then the FileDescriptor is also released.
	*/
	runningFinalize.set(Boolean.TRUE);
	try {
	close();
	} finally {
	runningFinalize.set(Boolean.FALSE);
	}
	}
	}
	}

	private native void close0() throws IOException;

	private static native void initIDs();

	static {
	initIDs();
	}

	}