1 /*

     2  * Copyright 1995-2007 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Sun designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Sun in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 package java.net;

    27 

    28 import java.io.FileDescriptor;

    29 import java.io.FileOutputStream;

    30 import java.io.IOException;

    31 import java.nio.channels.FileChannel;

    32 

    33 /**

    34  * This stream extends FileOutputStream to implement a

    35  * SocketOutputStream. Note that this class should <b>NOT</b> be

    36  * public.

    37  *

    38  * @author      Jonathan Payne

    39  * @author      Arthur van Hoff

    40  */

    41 class SocketOutputStream extends FileOutputStream

    42 {

    43     static {

    44         init();

    45     }

    46 

    47     private AbstractPlainSocketImpl impl = null;

    48     private byte temp[] = new byte[1];

    49     private Socket socket = null;

    50 

    51     /**

    52      * Creates a new SocketOutputStream. Can only be called

    53      * by a Socket. This method needs to hang on to the owner Socket so

    54      * that the fd will not be closed.

    55      * @param impl the socket output stream inplemented

    56      */

    57     SocketOutputStream(AbstractPlainSocketImpl impl) throws IOException {

    58         super(impl.getFileDescriptor());

    59         this.impl = impl;

    60         socket = impl.getSocket();

    61     }

    62 

    63     /**

    64      * Returns the unique {@link java.nio.channels.FileChannel FileChannel}

    65      * object associated with this file output stream. </p>

    66      *

    67      * The <code>getChannel</code> method of <code>SocketOutputStream</code>

    68      * returns <code>null</code> since it is a socket based stream.</p>

    69      *

    70      * @return  the file channel associated with this file output stream

    71      *

    72      * @since 1.4

    73      * @spec JSR-51

    74      */

    75     public final FileChannel getChannel() {

    76         return null;

    77     }

    78 

    79     /**

    80      * Writes to the socket.

    81      * @param fd the FileDescriptor

    82      * @param b the data to be written

    83      * @param off the start offset in the data

    84      * @param len the number of bytes that are written

    85      * @exception IOException If an I/O error has occurred.

    86      */

    87     private native void socketWrite0(FileDescriptor fd, byte[] b, int off,

    88                                      int len) throws IOException;

    89 

    90     /**

    91      * Writes to the socket with appropriate locking of the

    92      * FileDescriptor.

    93      * @param b the data to be written

    94      * @param off the start offset in the data

    95      * @param len the number of bytes that are written

    96      * @exception IOException If an I/O error has occurred.

    97      */

    98     private void socketWrite(byte b[], int off, int len) throws IOException {

    99 

   100         if (len <= 0 || off < 0 || off + len > b.length) {

   101             if (len == 0) {

   102                 return;

   103             }

   104             throw new ArrayIndexOutOfBoundsException();

   105         }

   106 

   107         FileDescriptor fd = impl.acquireFD();

   108         try {

   109             socketWrite0(fd, b, off, len);

   110         } catch (SocketException se) {

   111             if (se instanceof sun.net.ConnectionResetException) {

   112                 impl.setConnectionResetPending();

   113                 se = new SocketException("Connection reset");

   114             }

   115             if (impl.isClosedOrPending()) {

   116                 throw new SocketException("Socket closed");

   117             } else {

   118                 throw se;

   119             }

   120         } finally {

   121             impl.releaseFD();

   122         }

   123     }

   124 

   125     /**

   126      * Writes a byte to the socket.

   127      * @param b the data to be written

   128      * @exception IOException If an I/O error has occurred.

   129      */

   130     public void write(int b) throws IOException {

   131         temp[0] = (byte)b;

   132         socketWrite(temp, 0, 1);

   133     }

   134 

   135     /**

   136      * Writes the contents of the buffer <i>b</i> to the socket.

   137      * @param b the data to be written

   138      * @exception SocketException If an I/O error has occurred.

   139      */

   140     public void write(byte b[]) throws IOException {

   141         socketWrite(b, 0, b.length);

   142     }

   143 

   144     /**

   145      * Writes <i>length</i> bytes from buffer <i>b</i> starting at

   146      * offset <i>len</i>.

   147      * @param b the data to be written

   148      * @param off the start offset in the data

   149      * @param len the number of bytes that are written

   150      * @exception SocketException If an I/O error has occurred.

   151      */

   152     public void write(byte b[], int off, int len) throws IOException {

   153         socketWrite(b, off, len);

   154     }

   155 

   156     /**

   157      * Closes the stream.

   158      */

   159     private boolean closing = false;

   160     public void close() throws IOException {

   161         // Prevent recursion. See BugId 4484411

   162         if (closing)

   163             return;

   164         closing = true;

   165         if (socket != null) {

   166             if (!socket.isClosed())

   167                 socket.close();

   168         } else

   169             impl.close();

   170         closing = false;

   171     }

   172 

   173     /**

   174      * Overrides finalize, the fd is closed by the Socket.

   175      */

   176     protected void finalize() {}

   177 

   178     /**

   179      * Perform class load-time initializations.

   180      */

   181     private native static void init();

   182 

   183 }