001 package com.croftsoft.core.net;
002
003 import java.io.*;
004 import java.net.*;
005 import java.util.*;
006
007 // Need to drop thread priority
008
009 /*********************************************************************
010 * PortServer creates a java.net.ServerSocket which accepts connections
011 * and passes them on to com.orbs.net.SocketServer threads.
012 *
013 * @version
014 * $Id: PortServer.java,v 1.2 2008/09/20 04:12:46 croft Exp $
015 * @since
016 * 1997-04-19
017 * @author
018 * <a href="https://www.croftsoft.com/">David Wallace Croft</a>
019 *********************************************************************/
020
021 public final class PortServer implements Runnable {
022 //////////////////////////////////////////////////////////////////////
023 //////////////////////////////////////////////////////////////////////
024
025 private static final String COPYRIGHT
026 = "PortServer (C) Copyright 1997 David Wallace Croft";
027
028 private static final int DEFAULT_PORT = 1234;
029
030 private static final String HELP
031 = "java com.orbs.net.PortServer <classname> <port> <filename>\n"
032 + "\n"
033 + "<classname> must designate a class that implements\n"
034 + "com.orbs.net.SocketServer.\n"
035 + "\n"
036 + "If <port> is not specified, the default value of\n"
037 + DEFAULT_PORT + " will be used.\n"
038 + "\n"
039 + "If <shutdown_semaphore_filename> is specified and the file\n"
040 + "does not exist, the program will not start. If the file is\n"
041 + "deleted, shutdown will occur immediately after the next\n"
042 + "connection.\n";
043
044 private Class serverClass;
045 private int port;
046 private File semaphore;
047
048 private boolean shutdown = false;
049 private ServerSocket serverSocket;
050 private Thread thread;
051 private long nextUniqueID = 0;
052
053 private Vector thread_Vector = new Vector ( );
054 private Vector socket_Vector = new Vector ( );
055 private Vector server_Vector = new Vector ( );
056
057 //////////////////////////////////////////////////////////////////////
058 //////////////////////////////////////////////////////////////////////
059
060 /*********************************************************************
061 *********************************************************************/
062 public static final void main ( String [ ] args ) {
063 //////////////////////////////////////////////////////////////////////
064 System.out.println ( COPYRIGHT );
065 try {
066 Class serverClass = Class.forName ( args [ 0 ] );
067 int port = DEFAULT_PORT;
068 if ( args.length > 1 ) port = Integer.parseInt ( args [ 1 ] );
069 File semaphore = null;
070 if ( args.length > 2 ) semaphore = new File ( args [ 2 ] );
071 new PortServer ( serverClass, port, semaphore );
072 } catch ( Throwable t ) {
073 t.printStackTrace ( );
074 System.out.println ( HELP );
075 System.out.println ( t.getMessage ( ) );
076 return;
077 }
078 }
079
080 public PortServer (
081 Class serverClass, int port, File semaphore ) {
082 //////////////////////////////////////////////////////////////////////
083 boolean found = false;
084 Class [ ] interfaces = serverClass.getInterfaces ( );
085 for ( int i = 0; i < interfaces.length; i++ ) {
086 if ( interfaces [ i ].getName ( ).equals (
087 "com.croftsoft.core.net.SocketServer" ) ) {
088 found = true;
089 break;
090 }
091 }
092 if ( !found ) {
093 throw new RuntimeException (
094 "Class that implements com.orbs.net.SocketServer required." );
095 }
096 if ( ( port < 0 ) || ( port > 65535 ) ) {
097 throw new RuntimeException (
098 "Port number must be between 0 and 65535 inclusive." );
099 }
100 if ( ( semaphore != null ) && !semaphore.exists ( ) ) {
101 throw new RuntimeException (
102 "Semaphore file must be exist upon startup." );
103 }
104
105 this.serverClass = serverClass;
106 this.port = port;
107 this.semaphore = semaphore;
108
109 ( thread = new Thread ( this ) ).start ( );
110 }
111
112 public final void run ( ) {
113 //////////////////////////////////////////////////////////////////////
114 try {
115 serverSocket = new ServerSocket ( port );
116 while ( !shutdown ) {
117 if ( ( semaphore != null ) && !semaphore.exists ( ) ) {
118 throw new Exception ( "Semaphore file does not exist." );
119 }
120 synchronized ( thread_Vector ) {
121 Enumeration e = thread_Vector.elements ( );
122 while ( e.hasMoreElements ( ) ) {
123 Thread serverThread = ( Thread ) e.nextElement ( );
124 if ( !serverThread.isAlive ( ) ) {
125 terminate ( serverThread );
126 }
127 }
128 }
129 Socket socket = serverSocket.accept ( );
130 SocketServer socketServer
131 = ( SocketServer ) serverClass.newInstance ( );
132 socketServer.setPortServer ( this );
133 socketServer.setSocket ( socket );
134 socketServer.setUniqueID ( getNextUniqueID ( ) );
135 Thread serverThread = new Thread ( socketServer );
136 add ( socketServer, serverThread, socket );
137 serverThread.start ( );
138 }
139 } catch ( Throwable t ) { terminate ( t ); }
140 }
141
142 private synchronized final void add (
143 SocketServer socketServer, Thread serverThread, Socket socket ) {
144 //////////////////////////////////////////////////////////////////////
145 server_Vector.addElement ( socketServer );
146 thread_Vector.addElement ( serverThread );
147 socket_Vector.addElement ( socket );
148 }
149
150 public synchronized final void terminate ( Throwable t ) {
151 //////////////////////////////////////////////////////////////////////
152 if ( shutdown ) return;
153 shutdown = true;
154 if ( t != null ) t.printStackTrace ( );
155 Enumeration e = thread_Vector.elements ( );
156 while ( e.hasMoreElements ( ) ) {
157 terminate ( ( Thread ) e.nextElement ( ) );
158 }
159 try { serverSocket.close ( ); } catch ( Throwable t1 ) { }
160 try { thread.stop ( ); } catch ( Throwable t1 ) { }
161 }
162
163 public synchronized final void terminate (
164 SocketServer socketServer ) {
165 //////////////////////////////////////////////////////////////////////
166 int i = server_Vector.indexOf ( socketServer );
167 terminate ( i );
168 }
169
170 private synchronized final void terminate ( Thread thread ) {
171 //////////////////////////////////////////////////////////////////////
172 int i = thread_Vector.indexOf ( thread );
173 terminate ( i );
174 }
175
176 private synchronized final void terminate ( int i ) {
177 //////////////////////////////////////////////////////////////////////
178 if ( i < 0 ) return;
179 try { ( ( Socket ) socket_Vector.elementAt ( i ) ).close ( ); }
180 catch ( Throwable t1 ) { }
181 try { ( ( Thread ) thread_Vector.elementAt ( i ) ).stop ( ); }
182 catch ( Throwable t2 ) { }
183 try {
184 server_Vector.removeElementAt ( i );
185 socket_Vector.removeElementAt ( i );
186 thread_Vector.removeElementAt ( i );
187 } catch ( Throwable t ) {
188 t.printStackTrace ( );
189 }
190 }
191
192 public final Vector clone_server_Vector ( ) {
193 //////////////////////////////////////////////////////////////////////
194 return ( Vector ) server_Vector.clone ( );
195 }
196
197 private final synchronized long getNextUniqueID ( ) {
198 //////////////////////////////////////////////////////////////////////
199 return nextUniqueID++;
200 }
201
202 //////////////////////////////////////////////////////////////////////
203 //////////////////////////////////////////////////////////////////////
204 }