moved log4j.properties file from classes directory to sibling of properties file, which is specified by a servlet context parameter.

src/altk/comm/engine/CommEngine.java

@@ -19,6 +19,7 @@ import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 import org.apache.log4j.Logger;
+import org.apache.log4j.PropertyConfigurator;
 
 import altk.comm.engine.Broadcast.BroadcastState;
 import altk.comm.engine.exception.BroadcastError;
@@ -66,7 +67,7 @@ public abstract class CommEngine extends HttpServlet
      */
     protected EngineResources resources;
     
-    private static Logger myLogger = Logger.getLogger(CommEngine.class);
+    private static Logger myLogger;
     
     private ScheduledExecutorService scheduler;
 
@@ -97,13 +98,35 @@ public abstract class CommEngine extends HttpServlet
      */
     public final void init()
     {
-        myLogger.info("init() invoked");
         // check init parameters
         ServletContext servletContext = getServletContext();
         String propertiesFilePath;
         
         propertiesFilePath = servletContext.getInitParameter(getPropertiesContextName());
         File propertiesFile = new File(propertiesFilePath);
+        
+        // Configure log4j using log4j.properties file, \
+        // sibling to the engine properties file.
+        // This change is backward compatible with placing the log4j.properties file in
+        // the class path.
+        String log4j_properties = propertiesFile.getParent() + "/log4j.properties";
+        try
+        {
+            PropertyConfigurator.configure(log4j_properties);
+        }
+        catch (Exception e)
+        {
+            // Do nothing, assuming the exception is FileNotFoundException.
+            // Remaining log4j initialization will look for log4j.properties
+            // file in the class path.
+        }
+        // This activates Logger class instantiation.  At this point, if lo4j
+        // is not yet configured,
+        // it will look for the log4j.properties file in the class path.
+        myLogger = Logger.getLogger(CommEngine.class);
+        
+        myLogger.info("init() invoked");
+        CommonLogger.startup.info("Using lo4j properites file " + log4j_properties);
         CommonLogger.startup.info("Using configuration file " + propertiesFile.getAbsolutePath());
         config = new Properties();
         try