1 /*

        2  * Copyright (c) 1995, 2007, Oracle and/or its affiliates. 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.  Oracle designates this

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

        9  * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

       22  * or visit www.oracle.com if you need additional information or have any

       23  * 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 }