1 /* 2 * Copyright (c) 1995, 2018, 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 import jdk.internal.io.IOSupport; 31 32 /** 33 * This is the base class for network servers. To define a new type 34 * of server define a new subclass of NetworkServer with a serviceRequest 35 * method that services one request. Start the server by executing: 36 * <pre> 37 * new MyServerClass().startServer(port); 38 * </pre> 39 */ 40 public class NetworkServer implements Runnable, Cloneable { 41 /** Socket for communicating with client. */ 42 public Socket clientSocket = null; 43 private Thread serverInstance; 44 private ServerSocket serverSocket; 45 46 /** Stream for printing to the client. */ 47 public PrintStream clientOutput; 48 49 /** Buffered stream for reading replies from client. */ 50 public InputStream clientInput; 51 52 /** Close an open connection to the client. */ 53 public void close() throws IOException { 54 clientSocket.close(); 55 clientSocket = null; 56 clientInput = null; 57 clientOutput = null; 58 } 59 60 /** Return client connection status */ 61 public boolean clientIsOpen() { 62 return clientSocket != null; 63 } 64 65 public final void run() { 66 if (serverSocket != null) { 67 Thread.currentThread().setPriority(Thread.MAX_PRIORITY); 68 // System.out.print("Server starts " + serverSocket + "\n"); 69 while (true) { 70 try { 71 Socket ns = serverSocket.accept(); 72 // System.out.print("New connection " + ns + "\n"); 73 NetworkServer n = (NetworkServer)clone(); 74 n.serverSocket = null; 75 n.clientSocket = ns; 76 new Thread(null, n, "NetworkServer", 0, false).start(); 77 } catch(Exception e) { 78 System.out.print("Server failure\n"); 79 e.printStackTrace(); 80 try { 81 serverSocket.close(); 82 } catch(IOException e2) {} 83 System.out.print("cs="+serverSocket+"\n"); 84 break; 85 } 86 } 87 // close(); 88 } else { 89 try { 90 clientOutput = new PrintStream( 91 new BufferedOutputStream(clientSocket.getOutputStream()), 92 false, "ISO8859_1"); 93 clientInput = new BufferedInputStream(clientSocket.getInputStream()); 94 serviceRequest(); 95 // System.out.print("Service handler exits 96 // "+clientSocket+"\n"); 97 } catch(Exception e) { 98 // System.out.print("Service handler failure\n"); 99 // e.printStackTrace(); 100 } 101 try { 102 close(); 103 } catch(IOException e2) {} 104 } 105 } 106 107 /** Start a server on port <i>port</i>. It will call serviceRequest() 108 for each new connection. */ 109 public final void startServer(int port) throws IOException { 110 serverSocket = new ServerSocket(port, 50); 111 serverInstance = new Thread(null, this, "NetworkServer", 0, false); 112 serverInstance.start(); 113 } 114 115 /** Service one request. It is invoked with the clientInput and 116 clientOutput streams initialized. This method handles one client 117 connection. When it is done, it can simply exit. The default 118 server just echoes it's input. It is invoked in it's own private 119 thread. */ 120 public void serviceRequest() throws IOException { 121 clientOutput.print("Echo server " + getClass().getName() + "\n"); 122 clientOutput.flush(); 123 IOSupport.copy(clientInput, clientOutput, 300); 124 } 125 126 public static void main(String argv[]) { 127 try { 128 new NetworkServer ().startServer(8888); 129 } catch (IOException e) { 130 System.out.print("Server failed: "+e+"\n"); 131 } 132 } 133 134 /** 135 * Clone this object; 136 */ 137 public Object clone() { 138 try { 139 return super.clone(); 140 } catch (CloneNotSupportedException e) { 141 // this shouldn't happen, since we are Cloneable 142 throw new InternalError(e); 143 } 144 } 145 146 public NetworkServer () { 147 } 148 }