| career | drupal | java | mac | mysql | perl | scala | uml | unix  

What this is

This file is included in the "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Other links

The source code

 * Copyright (C) The Apache Software Foundation. All rights reserved.
 * This software is published under the terms of the Apache Software
 * License version 1.1, a copy of which has been included with this
 * distribution in the LICENSE.txt file.  */


import java.util.Hashtable;

import org.apache.log4j.*;
import org.apache.log4j.spi.*;

   A {@link SocketNode} based server that uses a different hierarchy
   for each client.

     Usage: java port configFile configDir

     where port is a part number where the server listens,
           configFile is a configuration file fed to the {@link PropertyConfigurator} and
           configDir is a path to a directory containing configuration files, possibly one for each client host.

The configFile is used to configure the log4j default hierarchy that the SocketServer will use to report on its actions.

When a new connection is opened from a previously unknown host, say, then the SocketServer will search for a configuration file called under the directory configDir that was passed as the third argument. If the file can be found, then a new hierarchy is instantiated and configured using the configuration file If and when the host opens another connection to the server, then the previously configured hierarchy is used.

In case there is no file called under the directory configDir, then the generic hierarchy is used. The generic hierarchy is configured using a configuration file called generic.lcf under the configDir directory. If no such file exists, then the generic hierarchy will be identical to the log4j default hierarchy.

Having different client hosts log using different hierarchies ensures the total independence of the clients with respect to their logging settings.

Currently, the hierarchy that will be used for a given request depends on the IP address of the client host. For example, two separate applicatons running on the same host and logging to the same server will share the same hierarchy. This is perfectly safe except that it might not provide the right amount of independence between applications. The SocketServer is intended as an example to be enhanced in order to implement more elaborate policies. @author Ceki Gülcü @since 1.0 */ public class SocketServer { static String GENERIC = "generic"; static String CONFIG_FILE_EXT = ".lcf"; static Category cat = Category.getInstance(SocketServer.class); static SocketServer server; static int port; // key=inetAddress, value=hierarchy Hashtable hierarchyMap; LoggerRepository genericHierarchy; File dir; public static void main(String argv[]) { if(argv.length == 3) init(argv[0], argv[1], argv[2]); else usage("Wrong number of arguments."); try {"Listening on port " + port); ServerSocket serverSocket = new ServerSocket(port); while(true) {"Waiting to accept a new client."); Socket socket = serverSocket.accept(); InetAddress inetAddress = socket.getInetAddress();"Connected to client at " + inetAddress); LoggerRepository h = (LoggerRepository) server.hierarchyMap.get(inetAddress); if(h == null) { h = server.configureHierarchy(inetAddress); }"Starting new socket node."); new Thread(new SocketNode(socket, h)).start(); } } catch(Exception e) { e.printStackTrace(); } } static void usage(String msg) { System.err.println(msg); System.err.println( "Usage: java " +SocketServer.class.getName() + " port configFile directory"); System.exit(1); } static void init(String portStr, String configFile, String dirStr) { try { port = Integer.parseInt(portStr); } catch(java.lang.NumberFormatException e) { e.printStackTrace(); usage("Could not interpret port number ["+ portStr +"]."); } PropertyConfigurator.configure(configFile); File dir = new File(dirStr); if(!dir.isDirectory()) { usage("["+dirStr+"] is not a directory."); } server = new SocketServer(dir); } public SocketServer(File directory) { this.dir = directory; hierarchyMap = new Hashtable(11); } // This method assumes that there is no hiearchy for inetAddress // yet. It will configure one and return it. LoggerRepository configureHierarchy(InetAddress inetAddress) {"Locating configuration file for "+inetAddress); // We assume that the toSting method of InetAddress returns is in // the format hostname/d1.d2.d3.d4 e.g. torino/ String s = inetAddress.toString(); int i = s.indexOf("/"); if(i == -1) { cat.warn("Could not parse the inetAddress ["+inetAddress+ "]. Using default hierarchy."); return genericHierarchy(); } else { String key = s.substring(0, i); File configFile = new File(dir, key+CONFIG_FILE_EXT); if(configFile.exists()) { Hierarchy h = new Hierarchy(new RootCategory((Level) Priority.DEBUG)); hierarchyMap.put(inetAddress, h); new PropertyConfigurator().doConfigure(configFile.getAbsolutePath(), h); return h; } else { cat.warn("Could not find config file ["+configFile+"]."); return genericHierarchy(); } } } LoggerRepository genericHierarchy() { if(genericHierarchy == null) { File f = new File(dir, GENERIC+CONFIG_FILE_EXT); if(f.exists()) { genericHierarchy = new Hierarchy(new RootCategory((Level) Priority.DEBUG)); new PropertyConfigurator().doConfigure(f.getAbsolutePath(), genericHierarchy); } else { cat.warn("Could not find config file ["+f+ "]. Will use the default hierarchy."); genericHierarchy = LogManager.getLoggerRepository(); } } return genericHierarchy; } }

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller


new blog posts


Copyright 1998-2021 Alvin Alexander,
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.