/* * Copyright 2004 Sun Microsystems, Inc. All Rights Reserved. * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * -Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * -Redistribution in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * Neither the name of Sun Microsystems, Inc. or the names of * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * This software is provided "AS IS," without a warranty of any * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY * EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL * NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF * USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR * ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, * SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF * THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS BEEN * ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that Software is not designed, licensed or * intended for use in the design, construction, operation or * maintenance of any nuclear facility. */ package example.inetd; import java.io.IOException; import java.io.File; import java.io.FileOutputStream; import java.io.PrintStream; import java.rmi.Remote; import java.rmi.RemoteException; import java.rmi.server.UnicastRemoteObject; /** * Used to launch a server from inetd. The main * method of this server implementation exports the service object (an * instance of ServiceInterface) and then uses the utility * method InitializeRegistry.initializeWithInheritedChannel to * create and export a registry using an inherited channel (if any) and * to bind a name to the service proxy in that registry for clients to look * up. * *

This program, when configured to be started from inetd, * will start the server when a client attempts to look up the server by * name in the registry on the port configured with inetd. * *

To configure inetd to launch this program, the following * entry should be added to the configuration file * /etc/inetd.conf: * *

 *    example-server stream tcp wait nobody jrehome/bin/java \
 *	  java -classpath classpath example.inetd.Server
 * 
* where jrehome is the path to the installed JRE, and * classpath is the class path for the example. * *

Additionally, the example-server name needs to be * configured as a service in the /etc/services file as * follows: * *

 *    example-server    port/tcp
 * 
* where port is the port the registry will accept requests * on. Note that the service name-- * here we used example-server-- can be another name, as long * as the chosen name it is not already configured in /etc/services. * *

This program also supports being run from the command line. In this * case, there is no inherited channel, and the program will simply * create/export a remote service, create/export a registry on the port * number supplied as the command line argument, and then bind the * service's proxy in the registry for clients to look up. *

This program can be run from the command line as follows: * *

 *     java example.inetd.Server port
 * 
* where port is a nonzero port that the registry accepts * requests on. **/ public class Server implements ServiceInterface { public Server() {} public String sendMessage(String message) { System.out.println(message); return "received message: " + message; } public static void main(String[] args) { /* * Redirect System.err output to a file. */ redirectErrorOutput(); /* * Parse port argument. */ int port = 0; if (args.length > 0) { try { port = Integer.parseInt(args[0]); } catch (NumberFormatException e) { goodbye("malformed port argument", e); } } /* * Create and export service, and then bind in local registry using * inherited channel, if any. */ ServiceInterface server = new Server(); Remote proxy = null; try { /* * Use two argument exportObject method to make sure that * dynamic proxy can be used. */ proxy = UnicastRemoteObject.exportObject(server, 0); } catch (RemoteException e) { goodbye("exception exporting service", e); } try { InitializeRegistry.initializeWithInheritedChannel( proxy, "ServiceInterface", port); } catch (IllegalArgumentException e) { goodbye("invalid port argument", e); } catch (Exception e) { goodbye("exception occurred", e); } System.err.println("ready"); /* * Wait forever. */ try { Thread.sleep(Long.MAX_VALUE); } catch (InterruptedException e) { throw new AssertionError(e); } } /** * Redirects System.err output to a file. */ private static void redirectErrorOutput() { try { File file = File.createTempFile("example-server-err", null, null); PrintStream errStream = new PrintStream(new FileOutputStream(file)); System.setErr(errStream); } catch (IOException e) { goodbye("exception setting up error output file", e); } } /** * Prints message and exception, then exits. */ private static void goodbye(String message, Exception e) { System.err.println("Server: " + message + ": "); e.printStackTrace(); System.exit(1); } }