1 /* 2 * Copyright (c) 1995, 2011, 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 package sun.net; 26 27 import java.io.*; 28 import java.net.Socket; 29 import java.net.ServerSocket; 30 31 /** 32 * This is the base class for network servers. To define a new type 33 * of server define a new subclass of NetworkServer with a serviceRequest 34 * method that services one request. Start the server by executing: 35 * <pre> 36 * new MyServerClass().startServer(port); 37 * </pre> 38 */ 39 public class NetworkServer implements Runnable, Cloneable { 40 /** Socket for communicating with client. */ 41 public Socket clientSocket = null; 42 private Thread serverInstance; 43 private ServerSocket serverSocket; 44 45 /** Stream for printing to the client. */ 46 public PrintStream clientOutput; 47 48 /** Buffered stream for reading replies from client. */ 49 public InputStream clientInput; 50 51 /** Close an open connection to the client. */ 52 public void close() throws IOException { 53 clientSocket.close(); 54 clientSocket = null; 55 clientInput = null; 56 clientOutput = null; 57 } 58 59 /** Return client connection status */ 60 public boolean clientIsOpen() { 61 return clientSocket != null; 62 } 63 64 public final void run() { 65 if (serverSocket != null) { 66 Thread.currentThread().setPriority(Thread.MAX_PRIORITY); 67 // System.out.print("Server starts " + serverSocket + "\n"); 68 while (true) { 69 try { 70 Socket ns = serverSocket.accept(); 71 // System.out.print("New connection " + ns + "\n"); 72 NetworkServer n = (NetworkServer)clone(); 73 n.serverSocket = null; 74 n.clientSocket = ns; 75 new Thread(null, n, "NetworkServer", 0, false).start(); 76 } catch(Exception e) { 77 System.out.print("Server failure\n"); 78 e.printStackTrace(); 79 try { 80 serverSocket.close(); 81 } catch(IOException e2) {} 82 System.out.print("cs="+serverSocket+"\n"); 83 break; 84 } 85 } 86 // close(); 87 } else { 88 try { 89 clientOutput = new PrintStream( 90 new BufferedOutputStream(clientSocket.getOutputStream()), 91 false, "ISO8859_1"); 92 clientInput = new BufferedInputStream(clientSocket.getInputStream()); 93 serviceRequest(); 94 // System.out.print("Service handler exits 95 // "+clientSocket+"\n"); 96 } catch(Exception e) { 97 // System.out.print("Service handler failure\n"); 98 // e.printStackTrace(); 99 } 100 try { 101 close(); 102 } catch(IOException e2) {} 103 } 104 } 105 106 /** Start a server on port <i>port</i>. It will call serviceRequest() 107 for each new connection. */ 108 public final void startServer(int port) throws IOException { 109 serverSocket = new ServerSocket(port, 50); 110 serverInstance = new Thread(null, this, "NetworkServer", 0, false); 111 serverInstance.start(); 112 } 113 114 /** Service one request. It is invoked with the clientInput and 115 clientOutput streams initialized. This method handles one client 116 connection. When it is done, it can simply exit. The default 117 server just echoes it's input. It is invoked in it's own private 118 thread. */ 119 public void serviceRequest() throws IOException { 120 byte buf[] = new byte[300]; 121 int n; 122 clientOutput.print("Echo server " + getClass().getName() + "\n"); 123 clientOutput.flush(); 124 while ((n = clientInput.read(buf, 0, buf.length)) >= 0) { 125 clientOutput.write(buf, 0, n); 126 } 127 } 128 129 public static void main(String argv[]) { 130 try { 131 new NetworkServer ().startServer(8888); 132 } catch (IOException e) { 133 System.out.print("Server failed: "+e+"\n"); 134 } 135 } 136 137 /** 138 * Clone this object; 139 */ 140 public Object clone() { 141 try { 142 return super.clone(); 143 } catch (CloneNotSupportedException e) { 144 // this shouldn't happen, since we are Cloneable 145 throw new InternalError(e); 146 } 147 } 148 149 public NetworkServer () { 150 } 151 }