1 /* 2 * Copyright (c) 1995, 2019, 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 static { init()43 init(); 44 } 45 46 private AbstractPlainSocketImpl impl = null; 47 private byte temp[] = new byte[1]; 48 49 /** 50 * Creates a new SocketOutputStream. Can only be called 51 * by a Socket. This method needs to hang on to the owner Socket so 52 * that the fd will not be closed. 53 * @param impl the socket output stream implemented 54 */ SocketOutputStream(AbstractPlainSocketImpl impl)55 SocketOutputStream(AbstractPlainSocketImpl impl) throws IOException { 56 super(impl.getFileDescriptor()); 57 this.impl = impl; 58 } 59 60 /** 61 * Returns the unique {@link java.nio.channels.FileChannel FileChannel} 62 * object associated with this file output stream. </p> 63 * 64 * The {@code getChannel} method of {@code SocketOutputStream} 65 * returns {@code null} since it is a socket based stream.</p> 66 * 67 * @return the file channel associated with this file output stream 68 * 69 * @since 1.4 70 */ getChannel()71 public final FileChannel getChannel() { 72 return null; 73 } 74 75 /** 76 * Writes to the socket. 77 * @param fd the FileDescriptor 78 * @param b the data to be written 79 * @param off the start offset in the data 80 * @param len the number of bytes that are written 81 * @throws IOException If an I/O error has occurred. 82 */ socketWrite0(FileDescriptor fd, byte[] b, int off, int len)83 private native void socketWrite0(FileDescriptor fd, byte[] b, int off, 84 int len) throws IOException; 85 86 /** 87 * Writes to the socket with appropriate locking of the 88 * FileDescriptor. 89 * @param b the data to be written 90 * @param off the start offset in the data 91 * @param len the number of bytes that are written 92 * @throws IOException If an I/O error has occurred. 93 */ socketWrite(byte b[], int off, int len)94 private void socketWrite(byte b[], int off, int len) throws IOException { 95 96 97 if (len <= 0 || off < 0 || len > b.length - off) { 98 if (len == 0) { 99 return; 100 } 101 throw new ArrayIndexOutOfBoundsException("len == " + len 102 + " off == " + off + " buffer length == " + b.length); 103 } 104 105 FileDescriptor fd = impl.acquireFD(); 106 try { 107 socketWrite0(fd, b, off, len); 108 } catch (SocketException se) { 109 if (impl.isClosedOrPending()) { 110 throw new SocketException("Socket closed"); 111 } else { 112 throw se; 113 } 114 } finally { 115 impl.releaseFD(); 116 } 117 } 118 119 /** 120 * Writes a byte to the socket. 121 * @param b the data to be written 122 * @throws IOException If an I/O error has occurred. 123 */ write(int b)124 public void write(int b) throws IOException { 125 temp[0] = (byte)b; 126 socketWrite(temp, 0, 1); 127 } 128 129 /** 130 * Writes the contents of the buffer <i>b</i> to the socket. 131 * @param b the data to be written 132 * @throws SocketException If an I/O error has occurred. 133 */ write(byte b[])134 public void write(byte b[]) throws IOException { 135 socketWrite(b, 0, b.length); 136 } 137 138 /** 139 * Writes <i>length</i> bytes from buffer <i>b</i> starting at 140 * offset <i>len</i>. 141 * @param b the data to be written 142 * @param off the start offset in the data 143 * @param len the number of bytes that are written 144 * @throws SocketException If an I/O error has occurred. 145 */ write(byte b[], int off, int len)146 public void write(byte b[], int off, int len) throws IOException { 147 socketWrite(b, off, len); 148 } 149 close()150 public void close() throws IOException { 151 // No longer used. Socket.getOutputStream returns an 152 // OutputStream which calls Socket.close directly 153 assert false; 154 } 155 156 /** 157 * Overrides finalize, the fd is closed by the Socket. 158 */ 159 @SuppressWarnings({"deprecation", "removal"}) finalize()160 protected void finalize() {} 161 162 /** 163 * Perform class load-time initializations. 164 */ init()165 private static native void init(); 166 167 } 168