Merge branch 'master' of https://github.com/decebals/pf4j

36 files changed, 713 insertions, 306 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..00a7233
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+target/
+.classpath
+.project
+.settings
+
diff --git a/demo/api/pom.xml b/demo/api/pom.xml
index 2a2a04b..1818ec5 100644
--- a/demo/api/pom.xml
+++ b/demo/api/pom.xml
@@ -4,12 +4,12 @@
     <parent>
         <groupId>ro.fortsoft.pf4j.demo</groupId>
         <artifactId>pf4j-demo-parent</artifactId>
-        <version>0.5-SNAPSHOT</version>
+        <version>0.6-SNAPSHOT</version>
     </parent>
 
     <modelVersion>4.0.0</modelVersion>
     <artifactId>pf4j-demo-api</artifactId>
-    <version>0.5-SNAPSHOT</version>
+    <version>0.6-SNAPSHOT</version>
     <packaging>jar</packaging>
     <name>Demo Api</name>
 
diff --git a/demo/app/pom.xml b/demo/app/pom.xml
index cef9586..bf07815 100644
--- a/demo/app/pom.xml
+++ b/demo/app/pom.xml
@@ -4,12 +4,12 @@
     <parent>
         <groupId>ro.fortsoft.pf4j.demo</groupId>
         <artifactId>pf4j-demo-parent</artifactId>
-        <version>0.5-SNAPSHOT</version>
+        <version>0.6-SNAPSHOT</version>
     </parent>
 
     <modelVersion>4.0.0</modelVersion>
     <artifactId>pf4j-demo-app</artifactId>
-    <version>0.5-SNAPSHOT</version>
+    <version>0.6-SNAPSHOT</version>
     <packaging>jar</packaging>
     <name>Demo App</name>
 
diff --git a/demo/app/src/main/java/ro/fortsoft/pf4j/demo/Boot.java b/demo/app/src/main/java/ro/fortsoft/pf4j/demo/Boot.java
index 9f218cf..7681a75 100644
--- a/demo/app/src/main/java/ro/fortsoft/pf4j/demo/Boot.java
+++ b/demo/app/src/main/java/ro/fortsoft/pf4j/demo/Boot.java
@@ -12,12 +12,19 @@
  */
 package ro.fortsoft.pf4j.demo;
 
+import java.io.File;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
+import java.util.NoSuchElementException;
 
 import org.apache.commons.lang.StringUtils;
 
 import ro.fortsoft.pf4j.DefaultPluginManager;
+import ro.fortsoft.pf4j.PluginClasspath;
+import ro.fortsoft.pf4j.PluginDescriptorFinder;
 import ro.fortsoft.pf4j.PluginManager;
+import ro.fortsoft.pf4j.PropertiesPluginDescriptorFinder;
 import ro.fortsoft.pf4j.demo.api.Greeting;
 
 /**
@@ -26,21 +33,25 @@ import ro.fortsoft.pf4j.demo.api.Greeting;
  * @author Decebal Suiu
  */
 public class Boot {
-
+	
     public static void main(String[] args) {
     	// print logo
     	printLogo();
     	
-        // load and start (active/resolved) plugins
-        final PluginManager pluginManager = new DefaultPluginManager();
+    	// create the plugin manager
+        final PluginManager pluginManager = createPluginManager();
+        
+        // load and start (active/resolved) the plugins
         pluginManager.loadPlugins();
         pluginManager.startPlugins();
         
+        // retrieves the extensions for Greeting extension point 
         List<Greeting> greetings = pluginManager.getExtensions(Greeting.class);
         for (Greeting greeting : greetings) {
         	System.out.println(">>> " + greeting.getGreeting());
         }
         
+        // stop the plugins
         pluginManager.stopPlugins();
         /*
         Runtime.getRuntime().addShutdownHook(new Thread() {
@@ -53,11 +64,82 @@ public class Boot {
         });
         */
     }
+    
+    private static PluginManager createPluginManager() {
+    	// retrieves the pf4j runtime mode
+    	String modeAsString = System.getProperty("pf4j.mode", RuntimeMode.PROD.toString());
+    	RuntimeMode mode = RuntimeMode.byName(modeAsString);
+
+    	System.out.println("PF4J runtime mode: '" + mode + "'");
+    	
+    	// create the plugin manager depending on runtime mode
+    	PluginManager pluginManager = null;
+    	if (mode == RuntimeMode.PROD) {
+    		pluginManager = new DefaultPluginManager();
+    	} else if (mode == RuntimeMode.DEV) {
+    		// run from eclipse IDE (for example)
+    		pluginManager = new DefaultPluginManager(new File("../plugins")) {
+
+				@Override
+				protected PluginClasspath createPluginClasspath() {
+					PluginClasspath pluginClasspath = super.createPluginClasspath();
+					// modify plugin classes
+					List<String> pluginClasses = pluginClasspath.getClassesDirectories();
+					pluginClasses.clear();
+					pluginClasses.add("target/classes");
+					
+					return pluginClasspath;
+				}
+	
+				@Override
+				protected PluginDescriptorFinder createPluginDescriptorFinder() {
+					return new PropertiesPluginDescriptorFinder();
+				}
+				
+    		};
+        }
+    	    	
+    	return pluginManager;
+    }
 
 	private static void printLogo() {
     	System.out.println(StringUtils.repeat("#", 40));
     	System.out.println(StringUtils.center("PF4J-DEMO", 40));
     	System.out.println(StringUtils.repeat("#", 40));		
 	}
+	
+	public enum RuntimeMode {
+		
+		DEV("dev"), // development
+	    PROD("prod"); // production		
+
+	    private final String name;
+	    
+		private static final Map<String, RuntimeMode> map = new HashMap<String, RuntimeMode>();
+		
+		static {
+			for (RuntimeMode mode : RuntimeMode.values()) {
+				map.put(mode.name, mode);
+			}
+		}
+		
+		private RuntimeMode(final String name) {
+	        this.name = name;
+	    }
+
+	    @Override
+	    public String toString() {
+	        return name;
+	    }
+		
+	    public static RuntimeMode byName(String name) {
+	    	if (map.containsKey(name)) {
+	    		return map.get(name);
+	    	}
+
+	    	throw new NoSuchElementException("Cannot found PF4J runtime mode with name '" + name + "'");
+	    }
+	    
+	}
 
 }
diff --git a/demo/app/src/main/resources/log4j.properties b/demo/app/src/main/resources/log4j.properties
index f2160e8..3ac64fd 100644
--- a/demo/app/src/main/resources/log4j.properties
+++ b/demo/app/src/main/resources/log4j.properties
@@ -2,5 +2,5 @@ log4j.rootLogger=DEBUG,Console
 
 log4j.appender.Console=org.apache.log4j.ConsoleAppender
 log4j.appender.Console.layout=org.apache.log4j.PatternLayout
-log4j.appender.Console.layout.conversionPattern=%-5p - %-26.26c{1} - %m\n
+log4j.appender.Console.layout.conversionPattern=%-5p - %-32.32c{1} - %m\n
 
diff --git a/demo/plugin1/plugin.properties b/demo/plugins/plugin1/plugin.properties
index 4f95d99..4f95d99 100644
--- a/demo/plugin1/plugin.properties
+++ b/demo/plugins/plugin1/plugin.properties
diff --git a/demo/plugin1/pom.xml b/demo/plugins/plugin1/pom.xml
index 49cf1df..8fe5f7b 100644
--- a/demo/plugin1/pom.xml
+++ b/demo/plugins/plugin1/pom.xml
@@ -3,13 +3,13 @@
     
     <parent>
         <groupId>ro.fortsoft.pf4j.demo</groupId>
-        <artifactId>pf4j-demo-parent</artifactId>
-        <version>0.5-SNAPSHOT</version>
+        <artifactId>pf4j-demo-plugins</artifactId>
+        <version>0.6-SNAPSHOT</version>
     </parent>
 
     <modelVersion>4.0.0</modelVersion>
     <artifactId>pf4j-demo-plugin1</artifactId>
-    <version>0.5-SNAPSHOT</version>
+    <version>0.6-SNAPSHOT</version>
     <packaging>jar</packaging>
     <name>Demo Plugin #1</name>
 
diff --git a/demo/plugin1/src/main/assembly/assembly.xml b/demo/plugins/plugin1/src/main/assembly/assembly.xml
index 3fdc464..3fdc464 100644
--- a/demo/plugin1/src/main/assembly/assembly.xml
+++ b/demo/plugins/plugin1/src/main/assembly/assembly.xml
diff --git a/demo/plugin1/src/main/java/ro/fortsoft/pf4j/demo/welcome/WelcomePlugin.java b/demo/plugins/plugin1/src/main/java/ro/fortsoft/pf4j/demo/welcome/WelcomePlugin.java
index d10d3dd..d10d3dd 100644
--- a/demo/plugin1/src/main/java/ro/fortsoft/pf4j/demo/welcome/WelcomePlugin.java
+++ b/demo/plugins/plugin1/src/main/java/ro/fortsoft/pf4j/demo/welcome/WelcomePlugin.java
diff --git a/demo/plugin2/plugin.properties b/demo/plugins/plugin2/plugin.properties
index 0de45e6..0de45e6 100644
--- a/demo/plugin2/plugin.properties
+++ b/demo/plugins/plugin2/plugin.properties
diff --git a/demo/plugin2/pom.xml b/demo/plugins/plugin2/pom.xml
index b69f767..2bf0dd8 100644
--- a/demo/plugin2/pom.xml
+++ b/demo/plugins/plugin2/pom.xml
@@ -3,13 +3,13 @@
     
     <parent>
         <groupId>ro.fortsoft.pf4j.demo</groupId>
-        <artifactId>pf4j-demo-parent</artifactId>
-        <version>0.5-SNAPSHOT</version>
+        <artifactId>pf4j-demo-plugins</artifactId>
+        <version>0.6-SNAPSHOT</version>
     </parent>
 
     <modelVersion>4.0.0</modelVersion>
     <artifactId>pf4j-demo-plugin2</artifactId>
-    <version>0.5-SNAPSHOT</version>
+    <version>0.6-SNAPSHOT</version>
     <packaging>jar</packaging>
     <name>Demo Plugin #2</name>
 
diff --git a/demo/plugin2/src/main/assembly/assembly.xml b/demo/plugins/plugin2/src/main/assembly/assembly.xml
index 5cefe0d..5cefe0d 100644
--- a/demo/plugin2/src/main/assembly/assembly.xml
+++ b/demo/plugins/plugin2/src/main/assembly/assembly.xml
diff --git a/demo/plugin2/src/main/java/ro/fortsoft/pf4j/demo/hello/HelloPlugin.java b/demo/plugins/plugin2/src/main/java/ro/fortsoft/pf4j/demo/hello/HelloPlugin.java
index 8f12e23..8f12e23 100644
--- a/demo/plugin2/src/main/java/ro/fortsoft/pf4j/demo/hello/HelloPlugin.java
+++ b/demo/plugins/plugin2/src/main/java/ro/fortsoft/pf4j/demo/hello/HelloPlugin.java
diff --git a/demo/plugins/pom.xml b/demo/plugins/pom.xml
new file mode 100644
index 0000000..d451b31
--- /dev/null
+++ b/demo/plugins/pom.xml
@@ -0,0 +1,37 @@
+<?xml version="1.0"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    
+    <parent>
+        <groupId>ro.fortsoft.pf4j.demo</groupId>
+        <artifactId>pf4j-demo-parent</artifactId>
+        <version>0.6-SNAPSHOT</version>
+    </parent>
+
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>ro.fortsoft.pf4j.demo</groupId>
+    <artifactId>pf4j-demo-plugins</artifactId>
+    <version>0.6-SNAPSHOT</version>
+    <packaging>pom</packaging>
+    <name>Demo Plugins Parent</name>
+
+    <build>
+        <resources>
+            <resource>
+                <filtering>false</filtering>
+                <directory>src/main/java</directory>
+                <excludes>
+                    <exclude>**/*.java</exclude>
+                </excludes>
+            </resource>
+            <resource>
+                <directory>src/main/resources</directory>
+            </resource>
+        </resources>
+    </build>
+
+    <modules>
+        <module>plugin1</module>
+        <module>plugin2</module>
+    </modules>
+
+</project>
diff --git a/demo/pom.xml b/demo/pom.xml
index 76bd4d7..7d00cd7 100644
--- a/demo/pom.xml
+++ b/demo/pom.xml
@@ -4,13 +4,13 @@
     <parent>
         <groupId>ro.fortsoft.pf4j</groupId>
         <artifactId>pf4j-parent</artifactId>
-        <version>0.5-SNAPSHOT</version>
+        <version>0.6-SNAPSHOT</version>
     </parent>
 
     <modelVersion>4.0.0</modelVersion>
     <groupId>ro.fortsoft.pf4j.demo</groupId>
     <artifactId>pf4j-demo-parent</artifactId>
-    <version>0.5-SNAPSHOT</version>
+    <version>0.6-SNAPSHOT</version>
     <packaging>pom</packaging>
     <name>Demo Parent</name>
 
@@ -32,8 +32,7 @@
     <modules>
         <module>app</module>
         <module>api</module>
-        <module>plugin1</module>
-        <module>plugin2</module>
+        <module>plugins</module>
     </modules>
 
 </project>
diff --git a/pf4j/pom.xml b/pf4j/pom.xml
index 68b0710..0859a55 100644
--- a/pf4j/pom.xml
+++ b/pf4j/pom.xml
@@ -4,12 +4,12 @@
     <parent>
         <groupId>ro.fortsoft.pf4j</groupId>
         <artifactId>pf4j-parent</artifactId>
-        <version>0.5-SNAPSHOT</version>
+        <version>0.6-SNAPSHOT</version>
     </parent>
 
     <modelVersion>4.0.0</modelVersion>
     <artifactId>pf4j</artifactId>
-    <version>0.5-SNAPSHOT</version>
+    <version>0.6-SNAPSHOT</version>
     <packaging>jar</packaging>
     <name>PF4J</name>
     <description>Plugin Framework for Java</description>
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultExtensionFinder.java b/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultExtensionFinder.java
index 492a701..66c1936 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultExtensionFinder.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultExtensionFinder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 Decebal Suiu
+ * Copyright 2013 Decebal Suiu
  * 
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
  * the License. You may obtain a copy of the License in the LICENSE file, or at:
@@ -12,69 +12,16 @@
  */
 package ro.fortsoft.pf4j;
 
-import java.lang.reflect.AnnotatedElement;
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.List;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import net.java.sezpoz.Index;
-import net.java.sezpoz.IndexItem;
-
 /**
- * Using Sezpoz(http://sezpoz.java.net/) for extensions discovery.
+ * The default implementation for ExtensionFinder. 
+ * Now, this class it's a "link" to {@link ro.fortsoft.pf4j.SezpozExtensionFinder}.
  * 
  * @author Decebal Suiu
  */
-public class DefaultExtensionFinder implements ExtensionFinder {
+public class DefaultExtensionFinder extends SezpozExtensionFinder {
 
-	private static final Logger log = LoggerFactory.getLogger(DefaultExtensionFinder.class);
-	
-	private volatile List<IndexItem<Extension, Object>> indices;
-	private ClassLoader classLoader;
-	
 	public DefaultExtensionFinder(ClassLoader classLoader) {
-		this.classLoader = classLoader;
+		super(classLoader);
 	}
 	
-	@Override
-	public <T> List<ExtensionWrapper<T>> find(Class<T> type) {
-		log.debug("Find extensions for " + type);
-        List<ExtensionWrapper<T>> result = new ArrayList<ExtensionWrapper<T>>();
-		getIndices();
-//		System.out.println("indices =  "+ indices);
-		for (IndexItem<Extension, Object> item : indices) {
-            try {
-            	AnnotatedElement element = item.element();
-            	Class<?> extensionType = (Class<?>) element;
-            	log.debug("Checking extension type " + extensionType);
-            	if (type.isAssignableFrom(extensionType)) {
-                    Object instance = item.instance();
-                    if (instance != null) {
-                		log.debug("Added extension " + extensionType);
-						result.add(new ExtensionWrapper<T>(type.cast(instance), item.annotation().ordinal()));
-                    }
-                }
-            } catch (InstantiationException e) {
-            	log.error(e.getMessage(), e);
-			}
-		}
-		
-		return result;
-	}
-
-	 private List<IndexItem<Extension, Object>> getIndices() {
-         if (indices == null) {
-             indices = new ArrayList<IndexItem<Extension, Object>>(); 
-             Iterator<IndexItem<Extension, Object>> it = Index.load(Extension.class, Object.class, classLoader).iterator();
-             while (it.hasNext()) {
-            	 indices.add(it.next());
-             }
-         }
-         
-         return indices;
-     }
-	 
 }
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginDescriptorFinder.java b/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginDescriptorFinder.java
index 3e23ff1..144fc6e 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginDescriptorFinder.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginDescriptorFinder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 Decebal Suiu
+ * Copyright 2013 Decebal Suiu
  * 
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
  * the License. You may obtain a copy of the License in the LICENSE file, or at:
@@ -12,78 +12,16 @@
  */
 package ro.fortsoft.pf4j;
 
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.io.IOException;
-import java.util.jar.Attributes;
-import java.util.jar.Manifest;
-
-import ro.fortsoft.pf4j.util.StringUtils;
-
 /**
- * Read the plugin descriptor from the manifest file.
- *
+ * The default implementation for PluginDescriptorFinder. 
+ * Now, this class it's a "link" to {@link ro.fortsoft.pf4j.ManifestPluginDescriptorFinder}.
+ * 
  * @author Decebal Suiu
  */
-public class DefaultPluginDescriptorFinder implements PluginDescriptorFinder {
-
-	@Override
-	public PluginDescriptor find(File pluginRepository) throws PluginException {
-    	// TODO it's ok with classes/ ?
-        File manifestFile = new File(pluginRepository, "classes/META-INF/MANIFEST.MF");
-        if (!manifestFile.exists()) {
-            throw new PluginException("Cannot find '" + manifestFile + "' file");
-        }
-
-    	FileInputStream input = null;
-		try {
-			input = new FileInputStream(manifestFile);
-		} catch (FileNotFoundException e) {
-			// not happening 
-		}
-		
-    	Manifest manifest = null;
-        try {
-            manifest = new Manifest(input);
-        } catch (IOException e) {
-            throw new PluginException(e.getMessage(), e);
-        } finally {
-            try {
-				input.close();
-			} catch (IOException e) {
-				throw new PluginException(e.getMessage(), e);
-			}
-        } 
-        
-        PluginDescriptor pluginDescriptor = new PluginDescriptor();
-        
-        // TODO validate !!!
-        Attributes attrs = manifest.getMainAttributes();
-        String id = attrs.getValue("Plugin-Id");
-        if (StringUtils.isEmpty(id)) {
-        	throw new PluginException("Plugin-Id cannot be empty");
-        }
-        pluginDescriptor.setPluginId(id);
-        
-        String clazz = attrs.getValue("Plugin-Class");
-        if (StringUtils.isEmpty(clazz)) {
-        	throw new PluginException("Plugin-Class cannot be empty");
-        }
-        pluginDescriptor.setPluginClass(clazz);
-        
-        String version = attrs.getValue("Plugin-Version");
-        if (StringUtils.isEmpty(version)) {
-        	throw new PluginException("Plugin-Version cannot be empty");
-        }
-        pluginDescriptor.setPluginVersion(PluginVersion.createVersion(version));
-        
-        String provider = attrs.getValue("Plugin-Provider");
-        pluginDescriptor.setProvider(provider);        
-        String dependencies = attrs.getValue("Plugin-Dependencies");
-        pluginDescriptor.setDependencies(dependencies);
+public class DefaultPluginDescriptorFinder extends ManifestPluginDescriptorFinder {
 
-		return pluginDescriptor;
+	public DefaultPluginDescriptorFinder(PluginClasspath pluginClasspath) {
+		super(pluginClasspath);
 	}
     	
 }
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginManager.java b/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginManager.java
index 20aba2d..0c2628d 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginManager.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/DefaultPluginManager.java
@@ -13,7 +13,7 @@
 package ro.fortsoft.pf4j;
 
 import java.io.File;
-import java.io.FilenameFilter;
+import java.io.FileFilter;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -24,11 +24,14 @@ import java.util.Map;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import ro.fortsoft.pf4j.util.AndFileFilter;
 import ro.fortsoft.pf4j.util.CompoundClassLoader;
-import ro.fortsoft.pf4j.util.DirectoryFilter;
+import ro.fortsoft.pf4j.util.DirectoryFileFilter;
 import ro.fortsoft.pf4j.util.FileUtils;
+import ro.fortsoft.pf4j.util.HiddenFilter;
+import ro.fortsoft.pf4j.util.NotFileFilter;
 import ro.fortsoft.pf4j.util.Unzip;
-import ro.fortsoft.pf4j.util.ZipFilter;
+import ro.fortsoft.pf4j.util.ZipFileFilter;
 
 /**
  * Default implementation of the PluginManager interface.
@@ -44,9 +47,11 @@ public class DefaultPluginManager implements PluginManager {
      */
     private File pluginsDirectory;
 
-    private ExtensionFinder extensionFinder;
+    private final ExtensionFinder extensionFinder;
     
-    private PluginDescriptorFinder pluginDescriptorFinder;
+    private final PluginDescriptorFinder pluginDescriptorFinder;
+    
+    private final PluginClasspath pluginClasspath;
     
     /**
      * A map of plugins this manager is responsible for (the key is the 'pluginId').
@@ -111,17 +116,18 @@ public class DefaultPluginManager implements PluginManager {
         disabledPlugins = new ArrayList<String>();
         compoundClassLoader = new CompoundClassLoader();
         
+        pluginClasspath = createPluginClasspath();
         pluginDescriptorFinder = createPluginDescriptorFinder();
         extensionFinder = createExtensionFinder();
 
         try {
         	// create a list with plugin identifiers that should be only accepted by this manager (whitelist from plugins/enabled.txt file)
         	enabledPlugins = FileUtils.readLines(new File(pluginsDirectory, "enabled.txt"), true);
-        	log.info("Enabled plugins: " + enabledPlugins);
+        	log.info("Enabled plugins: {}", enabledPlugins);
         	
         	// create a list with plugin identifiers that should not be accepted by this manager (blacklist from plugins/disabled.txt file)
         	disabledPlugins = FileUtils.readLines(new File(pluginsDirectory, "disabled.txt"), true);
-        	log.info("Disabled plugins: " + disabledPlugins);
+        	log.info("Disabled plugins: {}", disabledPlugins);
         } catch (IOException e) {
         	log.error(e.getMessage(), e);
         }
@@ -160,7 +166,7 @@ public class DefaultPluginManager implements PluginManager {
     public void startPlugins() {
         for (PluginWrapper pluginWrapper : resolvedPlugins) {
             try {
-            	log.info("Start plugin '" + pluginWrapper.getDescriptor().getPluginId() + "'");
+            	log.info("Start plugin '{}'", pluginWrapper.getDescriptor().getPluginId());
 				pluginWrapper.getPlugin().start();
 				pluginWrapper.setPluginState(PluginState.STARTED);
 				startedPlugins.add(pluginWrapper);
@@ -179,7 +185,7 @@ public class DefaultPluginManager implements PluginManager {
     	Collections.reverse(startedPlugins);
         for (PluginWrapper pluginWrapper : startedPlugins) {
             try {
-            	log.info("Stop plugin '" + pluginWrapper.getDescriptor().getPluginId() + "'");
+            	log.info("Stop plugin '{}'", pluginWrapper.getDescriptor().getPluginId());
             	pluginWrapper.getPlugin().stop();
             	pluginWrapper.setPluginState(PluginState.STOPPED);
 			} catch (PluginException e) {
@@ -193,16 +199,17 @@ public class DefaultPluginManager implements PluginManager {
      */
     @Override
     public void loadPlugins() {
+    	log.debug("Lookup plugins in '{}'", pluginsDirectory.getAbsolutePath());
     	// check for plugins directory
         if (!pluginsDirectory.exists() || !pluginsDirectory.isDirectory()) {
-            log.error("No '" + pluginsDirectory + "' directory");
+            log.error("No '{}' directory", pluginsDirectory.getAbsolutePath());
             return;
         }
 
         // expand all plugin archives
-        FilenameFilter zipFilter = new ZipFilter();
-        String[] zipFiles = pluginsDirectory.list(zipFilter);
-        for (String zipFile : zipFiles) {
+        FileFilter zipFilter = new ZipFileFilter();
+        File[] zipFiles = pluginsDirectory.listFiles(zipFilter);
+        for (File zipFile : zipFiles) {
         	try {
 				expandPluginArchive(zipFile);
 			} catch (IOException e) {
@@ -211,15 +218,18 @@ public class DefaultPluginManager implements PluginManager {
         }
 
         // check for no plugins
-        FilenameFilter directoryFilter = new DirectoryFilter();
-        String[] directories = pluginsDirectory.list(directoryFilter);
+        List<FileFilter> filterList = new ArrayList<FileFilter>();
+        filterList.add(new DirectoryFileFilter());
+        filterList.add(new NotFileFilter(createHiddenPluginFilter()));
+        FileFilter pluginsFilter = new AndFileFilter(filterList);
+        File[] directories = pluginsDirectory.listFiles(pluginsFilter);
         if (directories.length == 0) {
         	log.info("No plugins");
         	return;
         }
 
         // load any plugin from plugins directory
-        for (String directory : directories) {
+        for (File directory : directories) {
             try {
                 loadPlugin(directory);
             } catch (PluginException e) {
@@ -268,15 +278,43 @@ public class DefaultPluginManager implements PluginManager {
         return null;
     }
 
-	private void loadPlugin(String fileName) throws PluginException {
-        // test for plugin directory
-        File pluginDirectory = new File(pluginsDirectory, fileName);
-        if (!pluginDirectory.isDirectory()) {
-            return;
-        }
-        
+	/**
+	 * Add the possibility to override the PluginDescriptorFinder. 
+	 */
+    protected PluginDescriptorFinder createPluginDescriptorFinder() {
+    	return new DefaultPluginDescriptorFinder(pluginClasspath);
+    }
+
+    /**
+     * Add the possibility to override the ExtensionFinder. 
+     */
+    protected ExtensionFinder createExtensionFinder() {
+    	return new DefaultExtensionFinder(compoundClassLoader);
+    }
+
+    /**
+     * Add the possibility to override the PluginClassPath. 
+     */
+    protected PluginClasspath createPluginClasspath() {
+    	return new PluginClasspath();
+    }
+    
+    protected boolean isPluginDisabled(String pluginId) {
+    	if (enabledPlugins.isEmpty()) {
+    		return disabledPlugins.contains(pluginId);
+    	}
+    	
+    	return !enabledPlugins.contains(pluginId);
+    }
+    
+    protected FileFilter createHiddenPluginFilter() {
+    	return new HiddenFilter();
+    }
+    
+	private void loadPlugin(File pluginDirectory) throws PluginException {
         // try to load the plugin
-        String pluginPath = "/".concat(fileName);
+		String pluginName = pluginDirectory.getName();
+        String pluginPath = "/".concat(pluginName);
 
         // test for plugin duplication
         if (plugins.get(pathToIdMap.get(pluginPath)) != null) {
@@ -284,28 +322,28 @@ public class DefaultPluginManager implements PluginManager {
         }
 
         // retrieves the plugin descriptor
-        log.debug("Find plugin descriptor '" + pluginPath + "'");
+        log.debug("Find plugin descriptor '{}'", pluginPath);
         PluginDescriptor pluginDescriptor = pluginDescriptorFinder.find(pluginDirectory);
         log.debug("Descriptor " + pluginDescriptor);
         String pluginClassName = pluginDescriptor.getPluginClass();
-        log.debug("Class '" + pluginClassName + "'" + " for plugin '" + pluginPath + "'");
+        log.debug("Class '{}' for plugin '{}'",  pluginClassName, pluginPath);
 
         // test for disabled plugin
         if (isPluginDisabled(pluginDescriptor.getPluginId())) {
-        	log.info("Plugin '" + pluginPath + "' is disabled");
+        	log.info("Plugin '{}' is disabled", pluginPath);
             return;
         }
 
         // load plugin
-        log.debug("Loading plugin '" + pluginPath + "'");
-        PluginLoader pluginLoader = new PluginLoader(this, pluginDescriptor, pluginDirectory);
+        log.debug("Loading plugin '{}'", pluginPath);
+        PluginLoader pluginLoader = new PluginLoader(this, pluginDescriptor, pluginDirectory, pluginClasspath);
         pluginLoader.load();
-        log.debug("Loaded plugin '" + pluginPath + "'");
+        log.debug("Loaded plugin '{}'", pluginPath);
         
         // create the plugin wrapper
-        log.debug("Creating wrapper for plugin '" + pluginPath + "'");
+        log.debug("Creating wrapper for plugin '{}'", pluginPath);
         PluginWrapper pluginWrapper = new PluginWrapper(pluginDescriptor, pluginPath, pluginLoader.getPluginClassLoader());
-        log.debug("Created wrapper '" + pluginWrapper + "' for plugin '" + pluginPath + "'");
+        log.debug("Created wrapper '{}' for plugin '{}'", pluginWrapper, pluginPath);
 
         String pluginId = pluginDescriptor.getPluginId();
 
@@ -318,37 +356,15 @@ public class DefaultPluginManager implements PluginManager {
         pluginClassLoaders.put(pluginId, pluginClassLoader);
     }
 
-	/**
-	 * Add the possibility to override the PluginDescriptorFinder. 
-	 */
-    protected PluginDescriptorFinder createPluginDescriptorFinder() {
-    	return new DefaultPluginDescriptorFinder();
-    }
-
-    /**
-     * Add the possibility to override the ExtensionFinder. 
-     */
-    protected ExtensionFinder createExtensionFinder() {
-    	return new DefaultExtensionFinder(compoundClassLoader);
-    }
-
-    protected boolean isPluginDisabled(String pluginId) {
-    	if (enabledPlugins.isEmpty()) {
-    		return disabledPlugins.contains(pluginId);
-    	}
-    	
-    	return !enabledPlugins.contains(pluginId);
-    }
-    
-    private void expandPluginArchive(String fileName) throws IOException {
-        File pluginArchiveFile = new File(pluginsDirectory, fileName);
+    private void expandPluginArchive(File pluginArchiveFile) throws IOException {
+    	String fileName = pluginArchiveFile.getName();
         long pluginArchiveDate = pluginArchiveFile.lastModified();
         String pluginName = fileName.substring(0, fileName.length() - 4);
         File pluginDirectory = new File(pluginsDirectory, pluginName);
         // check if exists directory or the '.zip' file is "newer" than directory
         if (!pluginDirectory.exists() || (pluginArchiveDate > pluginDirectory.lastModified())) {
-        	log.debug("Expand plugin archive '" + pluginArchiveFile + "' in '" + pluginDirectory + "'");
-            // create directorie for plugin
+        	log.debug("Expand plugin archive '{}' in '{}'", pluginArchiveFile, pluginDirectory);
+            // create directory for plugin
             pluginDirectory.mkdirs();
 
             // expand '.zip' file
@@ -369,7 +385,7 @@ public class DefaultPluginManager implements PluginManager {
         for (PluginWrapper pluginWrapper : resolvedPlugins) {
         	unresolvedPlugins.remove(pluginWrapper);
         	compoundClassLoader.addLoader(pluginWrapper.getPluginClassLoader());
-        	log.info("Plugin '" + pluginWrapper.getDescriptor().getPluginId() + "' resolved");
+        	log.info("Plugin '{}' resolved", pluginWrapper.getDescriptor().getPluginId());
         }
 	}
 	
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/DependencyResolver.java b/pf4j/src/main/java/ro/fortsoft/pf4j/DependencyResolver.java
index 8611fef..a64aef5 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/DependencyResolver.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/DependencyResolver.java
@@ -51,14 +51,14 @@ class DependencyResolver {
 			}
 		}
 
-		log.debug("Graph: " + graph);
+		log.debug("Graph: {}", graph);
 		List<String> pluginsId = graph.reverseTopologicalSort();
 
 		if (pluginsId == null) {
 			throw new CyclicDependencyException("Cyclic dependences !!!" + graph.toString());
 		}
 
-		log.debug("Plugins order: " + pluginsId);
+		log.debug("Plugins order: {}", pluginsId);
 		List<PluginWrapper> sortedPlugins = new ArrayList<PluginWrapper>();
 		for (String pluginId : pluginsId) {
 			sortedPlugins.add(getPlugin(pluginId));
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/ManifestPluginDescriptorFinder.java b/pf4j/src/main/java/ro/fortsoft/pf4j/ManifestPluginDescriptorFinder.java
new file mode 100644
index 0000000..fd82793
--- /dev/null
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/ManifestPluginDescriptorFinder.java
@@ -0,0 +1,102 @@
+/*
+ * Copyright 2012 Decebal Suiu
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
+ * the License. You may obtain a copy of the License in the LICENSE file, or at:
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package ro.fortsoft.pf4j;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.util.jar.Attributes;
+import java.util.jar.Manifest;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import ro.fortsoft.pf4j.util.StringUtils;
+
+/**
+ * Read the plugin descriptor from the manifest file.
+ *
+ * @author Decebal Suiu
+ */
+public class ManifestPluginDescriptorFinder implements PluginDescriptorFinder {
+
+	private static final Logger log = LoggerFactory.getLogger(ManifestPluginDescriptorFinder.class);
+	
+	private PluginClasspath pluginClasspath;
+	
+	public ManifestPluginDescriptorFinder(PluginClasspath pluginClasspath) {
+		this.pluginClasspath = pluginClasspath;
+	}
+
+	@Override
+	public PluginDescriptor find(File pluginRepository) throws PluginException {
+    	// TODO it's ok with first classes directory? Another idea is to specify in PluginClasspath the folder.
+		String classes = pluginClasspath.getClassesDirectories().get(0);
+        File manifestFile = new File(pluginRepository, classes + "/META-INF/MANIFEST.MF");
+        log.debug("Lookup plugin descriptor in '{}'", manifestFile);
+        if (!manifestFile.exists()) {
+            throw new PluginException("Cannot find '" + manifestFile + "' file");
+        }
+
+    	FileInputStream input = null;
+		try {
+			input = new FileInputStream(manifestFile);
+		} catch (FileNotFoundException e) {
+			// not happening 
+		}
+		
+    	Manifest manifest = null;
+        try {
+            manifest = new Manifest(input);
+        } catch (IOException e) {
+            throw new PluginException(e.getMessage(), e);
+        } finally {
+            try {
+				input.close();
+			} catch (IOException e) {
+				throw new PluginException(e.getMessage(), e);
+			}
+        } 
+        
+        PluginDescriptor pluginDescriptor = new PluginDescriptor();
+        
+        // TODO validate !!!
+        Attributes attrs = manifest.getMainAttributes();
+        String id = attrs.getValue("Plugin-Id");
+        if (StringUtils.isEmpty(id)) {
+        	throw new PluginException("Plugin-Id cannot be empty");
+        }
+        pluginDescriptor.setPluginId(id);
+        
+        String clazz = attrs.getValue("Plugin-Class");
+        if (StringUtils.isEmpty(clazz)) {
+        	throw new PluginException("Plugin-Class cannot be empty");
+        }
+        pluginDescriptor.setPluginClass(clazz);
+        
+        String version = attrs.getValue("Plugin-Version");
+        if (StringUtils.isEmpty(version)) {
+        	throw new PluginException("Plugin-Version cannot be empty");
+        }
+        pluginDescriptor.setPluginVersion(PluginVersion.createVersion(version));
+        
+        String provider = attrs.getValue("Plugin-Provider");
+        pluginDescriptor.setProvider(provider);        
+        String dependencies = attrs.getValue("Plugin-Dependencies");
+        pluginDescriptor.setDependencies(dependencies);
+
+		return pluginDescriptor;
+	}
+    	
+}
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/PluginClasspath.java b/pf4j/src/main/java/ro/fortsoft/pf4j/PluginClasspath.java
new file mode 100644
index 0000000..23cd8f6
--- /dev/null
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/PluginClasspath.java
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2013 Decebal Suiu
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
+ * the License. You may obtain a copy of the License in the LICENSE file, or at:
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package ro.fortsoft.pf4j;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * The classpath of the plugin after it was unpacked. 
+ * It contains classes directories and lib directories (directories that contains jars). 
+ * All directories are relativ to plugin repository.
+ * The default values are "classes" and "lib". 
+ * 
+ * @author Decebal Suiu
+ */
+public class PluginClasspath {
+
+	private static final String DEFAULT_CLASSES_DIRECTORY = "classes";
+	private static final String DEFAULT_LIB_DIRECTORY = "lib";
+	
+	private List<String> classesDirectories;
+	private List<String> libDirectories;
+	
+	public PluginClasspath() {
+		classesDirectories = new ArrayList<String>();
+		libDirectories = new ArrayList<String>();
+		
+		// add defaults
+		classesDirectories.add(DEFAULT_CLASSES_DIRECTORY);
+		libDirectories.add(DEFAULT_LIB_DIRECTORY);
+	}
+
+	public List<String> getClassesDirectories() {
+		return classesDirectories;
+	}
+
+	public void setClassesDirectories(List<String> classesDirectories) {
+		this.classesDirectories = classesDirectories;
+	}
+
+	public List<String> getLibDirectories() {
+		return libDirectories;
+	}
+
+	public void setLibDirectories(List<String> libDirectories) {
+		this.libDirectories = libDirectories;
+	}
+	
+}
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/PluginLoader.java b/pf4j/src/main/java/ro/fortsoft/pf4j/PluginLoader.java
index 78603f4..8bd2daa 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/PluginLoader.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/PluginLoader.java
@@ -13,15 +13,16 @@
 package ro.fortsoft.pf4j;
 
 import java.io.File;
-import java.io.FilenameFilter;
+import java.io.FileFilter;
 import java.net.MalformedURLException;
+import java.util.List;
 import java.util.Vector;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import ro.fortsoft.pf4j.util.DirectoryFilter;
-import ro.fortsoft.pf4j.util.JarFilter;
+import ro.fortsoft.pf4j.util.DirectoryFileFilter;
+import ro.fortsoft.pf4j.util.JarFileFilter;
 
 /**
  * Load all informations needed by a plugin.
@@ -40,25 +41,15 @@ class PluginLoader {
      */
     private File pluginRepository;
 
-    /*
-     * The directory with '.class' files.
-     */
-    private File classesDirectory;
-
-    /*
-     * The directory with '.jar' files.
-     */
-    private File libDirectory;
-
+    private PluginClasspath pluginClasspath;
     private PluginClassLoader pluginClassLoader;
 
-    public PluginLoader(PluginManager pluginManager, PluginDescriptor pluginDescriptor, File pluginRepository) {
+    public PluginLoader(PluginManager pluginManager, PluginDescriptor pluginDescriptor, File pluginRepository, PluginClasspath pluginClasspath) {
         this.pluginRepository = pluginRepository;
-        classesDirectory = new File(pluginRepository, "classes");
-        libDirectory = new File(pluginRepository, "lib");
+        this.pluginClasspath = pluginClasspath; 
         ClassLoader parent = getClass().getClassLoader(); 
         pluginClassLoader = new PluginClassLoader(pluginManager, pluginDescriptor, parent);        
-        log.debug("Created class loader " + pluginClassLoader);
+        log.debug("Created class loader {}", pluginClassLoader);
     }
 
     public File getPluginRepository() {
@@ -77,66 +68,76 @@ class PluginLoader {
        return loadClasses() && loadJars();
     }
 
-    private void getJars(Vector<String> v, File file) {
-        FilenameFilter jarFilter = new JarFilter();
-        FilenameFilter directoryFilter = new DirectoryFilter();
-
-        if (file.exists() && file.isDirectory() && file.isAbsolute()) {
-            String[] jars = file.list(jarFilter);
-            for (int i = 0; (jars != null) && (i < jars.length); ++i) {
-                v.addElement(jars[i]);
-            }
-
-            String[] directoryList = file.list(directoryFilter);
-            for (int i = 0; (directoryList != null) && (i < directoryList.length); ++i) {
-                File directory = new File(file, directoryList[i]);
-                getJars(v, directory);
-            }
-        }
-    }
-
     private boolean loadClasses() {
-        // make 'classesDirectory' absolute
-        classesDirectory = classesDirectory.getAbsoluteFile();
-
-        if (classesDirectory.exists() && classesDirectory.isDirectory()) {
-            log.debug("Found '" + classesDirectory.getPath() + "' directory");
-
-            try {
-                pluginClassLoader.addURL(classesDirectory.toURI().toURL());
-                log.debug("Added '" + classesDirectory + "' to the class loader path");
-            } catch (MalformedURLException e) {
-                e.printStackTrace();
-                log.error(e.getMessage(), e);
-                return false;
-            }
-        }
+    	List<String> classesDirectories = pluginClasspath.getClassesDirectories();
+    	
+    	// add each classes directory to plugin class loader
+    	for (String classesDirectory : classesDirectories) {
+	        // make 'classesDirectory' absolute
+	        File file = new File(pluginRepository, classesDirectory).getAbsoluteFile();
+	
+	        if (file.exists() && file.isDirectory()) {
+	            log.debug("Found '{}' directory", file.getPath());
+	
+	            try {
+	                pluginClassLoader.addURL(file.toURI().toURL());
+	                log.debug("Added '{}' to the class loader path", file);
+	            } catch (MalformedURLException e) {
+	                e.printStackTrace();
+	                log.error(e.getMessage(), e);
+	                return false;
+	            }
+	        }
+    	}
 
         return true;
     }
 
     /**
-     * Add all *.jar files from '/lib' directory.
+     * Add all *.jar files from lib directories to class loader.
      */
     private boolean loadJars() {
-        // make 'jarDirectory' absolute
-        libDirectory = libDirectory.getAbsoluteFile();
-
-        Vector<String> jars = new Vector<String>();
-        getJars(jars, libDirectory);
-        for (String jar : jars) {
-            File jarFile = new File(libDirectory, jar);
-            try {
-                pluginClassLoader.addURL(jarFile.toURI().toURL());
-                log.debug("Added '" + jarFile + "' to the class loader path");
-            } catch (MalformedURLException e) {
-                e.printStackTrace();
-                log.error(e.getMessage(), e);
-                return false;
-            }
-        }
+    	List<String> libDirectories = pluginClasspath.getLibDirectories();
+    	
+    	// add each jars directory to plugin class loader
+    	for (String libDirectory : libDirectories) {
+	        // make 'libDirectory' absolute
+	        File file = new File(pluginRepository, libDirectory).getAbsoluteFile();
+	
+	        // collect all jars from current lib directory in jars variable
+	        Vector<File> jars = new Vector<File>();
+	        getJars(jars, file);
+	        for (File jar : jars) {
+	            try {
+	                pluginClassLoader.addURL(jar.toURI().toURL());
+	                log.debug("Added '{}' to the class loader path", jar);
+	            } catch (MalformedURLException e) {
+	                e.printStackTrace();
+	                log.error(e.getMessage(), e);
+	                return false;
+	            }
+	        }
+    	}
 
         return true;
     }
 
+    private void getJars(Vector<File> bucket, File file) {
+        FileFilter jarFilter = new JarFileFilter();
+        FileFilter directoryFilter = new DirectoryFileFilter();
+
+        if (file.exists() && file.isDirectory() && file.isAbsolute()) {
+            File[] jars = file.listFiles(jarFilter);
+            for (int i = 0; (jars != null) && (i < jars.length); ++i) {
+                bucket.addElement(jars[i]);
+            }
+
+            File[] directories = file.listFiles(directoryFilter);
+            for (int i = 0; (directories != null) && (i < directories.length); ++i) {
+                File directory = directories[i];
+                getJars(bucket, directory);
+            }
+        }
+    }
+
 }
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/PropertiesPluginDescriptorFinder.java b/pf4j/src/main/java/ro/fortsoft/pf4j/PropertiesPluginDescriptorFinder.java
index 4f0e753..2c7c707 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/PropertiesPluginDescriptorFinder.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/PropertiesPluginDescriptorFinder.java
@@ -19,6 +19,9 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.util.Properties;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import ro.fortsoft.pf4j.util.StringUtils;
 
 /**
@@ -28,10 +31,14 @@ import ro.fortsoft.pf4j.util.StringUtils;
  */
 public class PropertiesPluginDescriptorFinder implements PluginDescriptorFinder {
 
+	private static final Logger log = LoggerFactory.getLogger(PropertiesPluginDescriptorFinder.class);
+	
+	private static final String DEFAULT_PROPERTIES_FILE_NAME = "plugin.properties";
+	
 	private String propertiesFileName;
 
 	public PropertiesPluginDescriptorFinder() {
-		this("plugin.properties");
+		this(DEFAULT_PROPERTIES_FILE_NAME);
 	}
 
 	public PropertiesPluginDescriptorFinder(String propertiesFileName) {
@@ -41,6 +48,7 @@ public class PropertiesPluginDescriptorFinder implements PluginDescriptorFinder
 	@Override
 	public PluginDescriptor find(File pluginRepository) throws PluginException {
         File propertiesFile = new File(pluginRepository, propertiesFileName);
+        log.debug("Lookup plugin descriptor in '{}'", propertiesFile);
         if (!propertiesFile.exists()) {
             throw new PluginException("Cannot find '" + propertiesFile + "' file");
         }
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/SezpozExtensionFinder.java b/pf4j/src/main/java/ro/fortsoft/pf4j/SezpozExtensionFinder.java
new file mode 100644
index 0000000..3f5014c
--- /dev/null
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/SezpozExtensionFinder.java
@@ -0,0 +1,80 @@
+/*
+ * Copyright 2012 Decebal Suiu
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
+ * the License. You may obtain a copy of the License in the LICENSE file, or at:
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package ro.fortsoft.pf4j;
+
+import java.lang.reflect.AnnotatedElement;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import net.java.sezpoz.Index;
+import net.java.sezpoz.IndexItem;
+
+/**
+ * Using Sezpoz(http://sezpoz.java.net/) for extensions discovery.
+ * 
+ * @author Decebal Suiu
+ */
+public class SezpozExtensionFinder implements ExtensionFinder {
+
+	private static final Logger log = LoggerFactory.getLogger(SezpozExtensionFinder.class);
+	
+	private volatile List<IndexItem<Extension, Object>> indices;
+	private ClassLoader classLoader;
+	
+	public SezpozExtensionFinder(ClassLoader classLoader) {
+		this.classLoader = classLoader;
+	}
+	
+	@Override
+	public <T> List<ExtensionWrapper<T>> find(Class<T> type) {
+		log.debug("Find extensions for {}", type);
+        List<ExtensionWrapper<T>> result = new ArrayList<ExtensionWrapper<T>>();
+		getIndices();
+//		System.out.println("indices =  "+ indices);
+		for (IndexItem<Extension, Object> item : indices) {
+            try {
+            	AnnotatedElement element = item.element();
+            	Class<?> extensionType = (Class<?>) element;
+            	log.debug("Checking extension type {}", extensionType);
+            	if (type.isAssignableFrom(extensionType)) {
+                    Object instance = item.instance();
+                    if (instance != null) {
+                		log.debug("Added extension {}", extensionType);
+						result.add(new ExtensionWrapper<T>(type.cast(instance), item.annotation().ordinal()));
+                    }
+                }
+            } catch (InstantiationException e) {
+            	log.error(e.getMessage(), e);
+			}
+		}
+		
+		return result;
+	}
+
+	 private List<IndexItem<Extension, Object>> getIndices() {
+         if (indices == null) {
+             indices = new ArrayList<IndexItem<Extension, Object>>(); 
+             Iterator<IndexItem<Extension, Object>> it = Index.load(Extension.class, Object.class, classLoader).iterator();
+             while (it.hasNext()) {
+            	 indices.add(it.next());
+             }
+         }
+         
+         return indices;
+     }
+	 
+}
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/AndFileFilter.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/AndFileFilter.java
new file mode 100644
index 0000000..b50e852
--- /dev/null
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/AndFileFilter.java
@@ -0,0 +1,76 @@
+/*
+ * Copyright 2013 Decebal Suiu
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
+ * the License. You may obtain a copy of the License in the LICENSE file, or at:
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package ro.fortsoft.pf4j.util;
+
+import java.io.File;
+import java.io.FileFilter;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+
+/**
+ * This filter providing conditional AND logic across a list of
+ * file filters. This filter returns <code>true</code> if all filters in the
+ * list return <code>true</code>. Otherwise, it returns <code>false</code>.
+ * Checking of the file filter list stops when the first filter returns
+ * <code>false</code>.
+ *
+ * @author Decebal Suiu
+ */
+public class AndFileFilter implements FileFilter {
+
+    /** The list of file filters. */
+    private List<FileFilter> fileFilters;
+
+    public AndFileFilter() {
+        this.fileFilters = new ArrayList<FileFilter>();
+    }
+
+    public AndFileFilter(List<FileFilter> fileFilters) {
+        this.fileFilters = new ArrayList<FileFilter>(fileFilters);
+    }
+
+    public void addFileFilter(FileFilter fileFilter) {
+        fileFilters.add(fileFilter);
+    }
+
+    public List<FileFilter> getFileFilters() {
+        return Collections.unmodifiableList(fileFilters);
+    }
+
+    public boolean removeFileFilter(FileFilter fileFilter) {
+        return fileFilters.remove(fileFilter);
+    }
+
+    public void setFileFilters(List<FileFilter> fileFilters) {
+        this.fileFilters = new ArrayList<FileFilter>(fileFilters);
+    }
+
+    @Override
+    public boolean accept(File file) {
+        if (this.fileFilters.size() == 0) {
+            return false;
+        }
+
+        for (Iterator<FileFilter> iter = this.fileFilters.iterator(); iter.hasNext();) {
+            FileFilter fileFilter = (FileFilter) iter.next();
+            if (!fileFilter.accept(file)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+}
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/DirectoryFilter.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/DirectoryFileFilter.java
index 54e1a95..3877222 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/util/DirectoryFilter.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/DirectoryFileFilter.java
@@ -14,22 +14,17 @@ package ro.fortsoft.pf4j.util;
 
 import java.io.File;
 import java.io.FileFilter;
-import java.io.FilenameFilter;
 
 /**
+ * Filter accepts files that are directories.
+ * 
  * @author Decebal Suiu
  */
-public class DirectoryFilter implements FileFilter, FilenameFilter {
+public class DirectoryFileFilter implements FileFilter {
 
-    /**
-     * Accepts any file ending in .jar. The case of the filename is ignored.
-     */
+	@Override
     public boolean accept(File file) {
         return file.isDirectory();
     }
 
-    public boolean accept(File dir, String name) {
-        return accept(new File(dir, name));
-    }
-
 }
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/ExtensionFilter.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/ExtensionFileFilter.java
index 22b999f..03ed0b7 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/util/ExtensionFilter.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/ExtensionFileFilter.java
@@ -13,29 +13,25 @@
 package ro.fortsoft.pf4j.util;
 
 import java.io.File;
-import java.io.FilenameFilter;
+import java.io.FileFilter;
 
 /**
+ * Filter accepts any file ending in extension. The case of the filename is ignored.
+ * 
  * @author Decebal Suiu
  */
-public class ExtensionFilter implements FilenameFilter {
+public class ExtensionFileFilter implements FileFilter {
 
     private String extension;
 
-    public ExtensionFilter(String extension) {
+    public ExtensionFileFilter(String extension) {
         this.extension = extension;
     }
 
-    /**
-     * Accepts any file ending in extension. The case of the filename is ignored.
-     */
+    @Override
     public boolean accept(File file) {
         // perform a case insensitive check.
         return file.getName().toUpperCase().endsWith(extension.toUpperCase());
     }
 
-    public boolean accept(File dir, String name) {
-        return accept(new File(dir, name));
-    }
-
 }
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/HiddenFilter.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/HiddenFilter.java
new file mode 100644
index 0000000..eed53f1
--- /dev/null
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/HiddenFilter.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2013 Decebal Suiu
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
+ * the License. You may obtain a copy of the License in the LICENSE file, or at:
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package ro.fortsoft.pf4j.util;
+
+import java.io.File;
+import java.io.FileFilter;
+
+/**
+ * Filter that only accepts hidden files.
+ * 
+ * @author decebal.suiu
+ */
+public class HiddenFilter implements FileFilter {
+
+	@Override
+	public boolean accept(File file) {
+		return file.isHidden();
+	}
+
+}
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/JarFilter.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/JarFileFilter.java
index 60c8859..5c1f0ca 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/util/JarFilter.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/JarFileFilter.java
@@ -18,14 +18,14 @@ package ro.fortsoft.pf4j.util;
  *
  * @author Decebal Suiu
  */
-public class JarFilter extends ExtensionFilter {
+public class JarFileFilter extends ExtensionFileFilter {
 
     /**
      * The extension that this filter will search for.
      */
     private static final String JAR_EXTENSION = ".JAR";
 
-    public JarFilter() {
+    public JarFileFilter() {
         super(JAR_EXTENSION);
     }
 
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/NotFileFilter.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/NotFileFilter.java
new file mode 100644
index 0000000..68ff3e0
--- /dev/null
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/NotFileFilter.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2013 Decebal Suiu
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
+ * the License. You may obtain a copy of the License in the LICENSE file, or at:
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package ro.fortsoft.pf4j.util;
+
+import java.io.File;
+import java.io.FileFilter;
+
+/**
+ * This filter produces a logical NOT of the filters specified.
+ *
+ * @author Decebal Suiu
+ */
+public class NotFileFilter implements FileFilter {
+
+    private FileFilter filter;
+
+    public NotFileFilter(FileFilter filter) {
+        this.filter = filter;
+    }
+
+    @Override
+    public boolean accept(File file) {
+        return !filter.accept(file);
+    }
+
+}
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/Unzip.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/Unzip.java
index e3f3ed3..74d60d5 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/util/Unzip.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/Unzip.java
@@ -61,7 +61,7 @@ public class Unzip {
     }
 
     public void extract() throws IOException {
-        log.debug("Extract content of " + source + " to " + destination);
+        log.debug("Extract content of '{}' to '{}'", source, destination);
 
         // delete destination file if exists
         removeDirectory(destination);
@@ -91,7 +91,7 @@ public class Unzip {
 		            fos.close();
                 }
     	    } catch (FileNotFoundException e) {
-    	    	log.error("File '" + zipEntry.getName() + "' not found");
+    	    	log.error("File '{}' not found", zipEntry.getName());
     	    }
 	    }
 
diff --git a/pf4j/src/main/java/ro/fortsoft/pf4j/util/ZipFilter.java b/pf4j/src/main/java/ro/fortsoft/pf4j/util/ZipFileFilter.java
index 4b10de3..9743fb6 100644
--- a/pf4j/src/main/java/ro/fortsoft/pf4j/util/ZipFilter.java
+++ b/pf4j/src/main/java/ro/fortsoft/pf4j/util/ZipFileFilter.java
@@ -18,14 +18,14 @@ package ro.fortsoft.pf4j.util;
  *
  * @author Decebal Suiu
  */
-public class ZipFilter extends ExtensionFilter {
+public class ZipFileFilter extends ExtensionFileFilter {
 
     /**
      * The extension that this filter will search for.
      */
     private static final String ZIP_EXTENSION = ".ZIP";
 
-    public ZipFilter() {
+    public ZipFileFilter() {
         super(ZIP_EXTENSION);
     }
 
diff --git a/pom.xml b/pom.xml
index 3c9bb2e..c54a45b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -10,7 +10,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>ro.fortsoft.pf4j</groupId>
     <artifactId>pf4j-parent</artifactId>
-    <version>0.5-SNAPSHOT</version>
+    <version>0.6-SNAPSHOT</version>
     <packaging>pom</packaging>
     <name>PF4J Parent</name>
     <description>Plugin Framework for Java</description>
diff --git a/run-demo.bat b/run-demo.bat
index 05c53df..0edca59 100644
--- a/run-demo.bat
+++ b/run-demo.bat
@@ -12,8 +12,8 @@ mkdir demo-dist\plugins
 
 REM copy artifacts to demo-dist folder
 xcopy demo\app\target\pf4j-demo-app-*.zip demo-dist /s /i
-xcopy demo\plugin1\target\pf4j-demo-plugin1-*.zip demo-dist\plugins /s
-xcopy demo\plugin2\target\pf4j-demo-plugin2-*.zip demo-dist\plugins /s
+xcopy demo\plugins\plugin1\target\pf4j-demo-plugin1-*.zip demo-dist\plugins /s
+xcopy demo\plugins\plugin2\target\pf4j-demo-plugin2-*.zip demo-dist\plugins /s
 
 cd demo-dist
 
diff --git a/run-demo.sh b/run-demo.sh
index ce68e5b..724d68b 100755
--- a/run-demo.sh
+++ b/run-demo.sh
@@ -14,8 +14,8 @@ mkdir demo-dist/plugins
 
 # copy artifacts to demo-dist folder
 cp -r demo/app/target/pf4j-demo-*/* demo-dist/
-cp demo/plugin1/target/pf4j-demo-plugin1-*.zip demo-dist/plugins/
-cp demo/plugin2/target/pf4j-demo-plugin2-*.zip demo-dist/plugins/
+cp demo/plugins/plugin1/target/pf4j-demo-plugin1-*.zip demo-dist/plugins/
+cp demo/plugins/plugin2/target/pf4j-demo-plugin2-*.zip demo-dist/plugins/
 
 # run demo
 cd demo-dist