Make it possible to configure our log factory programmatically.

git-svn-id: https://samskivert.googlecode.com/svn/trunk@2321 6335cc39-0255-0410-8fd6-9bcaacd3b74c

src/java/com/samskivert/util/Logger.java

@@ -39,6 +39,17 @@ package com.samskivert.util;
  */
 public abstract class Logger
 {
+    /**
+     * Used to create logger instances. This is only public so that the log factory can be
+     * configured programmatically via {@link Logger#setFactory}.
+     */
+    public static interface Factory
+    {
+        public void init ();
+        public Logger getLogger (String name);
+        public Logger getLogger (Class clazz);
+    }
+
     /**
      * Obtains a logger with the specified name.
      */
@@ -55,6 +66,18 @@ public abstract class Logger
         return _factory.getLogger(clazz);
     }
 
+    /**
+     * Configures the logging factory be used by the logging system. Normally you would not do this
+     * and would instead use the <code>com.samskivert.util.Logger</code> system property instead,
+     * but in some situations, like in an applet, you cannot pass system properties and we can't
+     * read them anyway because we're running in a security sandbox.
+     */
+    public static void setFactory (Factory factory)
+    {
+        _factory = factory;
+        _factory.init();
+    }
+
     /**
      * Logs a debug message.
      *
@@ -133,12 +156,12 @@ public abstract class Logger
     protected static void initLogger ()
     {
         // if a custom class was specified as a system property, use that
-        _factory = createConfiguredFactory();
+        Factory factory = createConfiguredFactory();
 
         // create and a log4j logger if the log4j configuration system property is set
         try {
-            if (_factory == null && System.getProperty("log4j.configuration") != null) {
-                _factory = (Factory)Class.forName("com.samskivert.util.Log4JLogger").newInstance();
+            if (factory == null && System.getProperty("log4j.configuration") != null) {
+                factory = (Factory)Class.forName("com.samskivert.util.Log4JLogger").newInstance();
             }
         } catch (SecurityException se) {
             // in a sandbox, no biggie
@@ -147,12 +170,12 @@ public abstract class Logger
         }
 
         // lastly, fall back to the Java logging system
-        if (_factory == null) {
-            _factory = new JDK14Logger();
+        if (factory == null) {
+            factory = new JDK14Logger();
         }
 
-        // and finally initialize our factory
-        _factory.init();
+        // and finally configure our factory
+        setFactory(factory);
     }
 
     /**
@@ -178,16 +201,6 @@ public abstract class Logger
         return null;
     }
 
-    /**
-     * Used to create logger instances.
-     */
-    protected static interface Factory
-    {
-        public void init ();
-        public Logger getLogger (String name);
-        public Logger getLogger (Class clazz);
-    }
-
     protected static Factory _factory;
 
     static {