corrected an error

Kieker.WebGUI/src/main/java/kieker/webgui/common/PluginClassLoader.java

@@ -26,10 +26,9 @@ import java.net.URLClassLoader;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
 import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.Iterator;
 import java.util.List;
-import java.util.Map;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 import kieker.analysis.AnalysisController;
 import kieker.analysis.model.analysisMetaModel.MIDependency;
@@ -53,17 +52,16 @@ public final class PluginClassLoader extends ClassLoader {
 	 * The singleton instance of this class.
 	 */
 	private static PluginClassLoader instance;
-    
-    private final List<URL> list = new ArrayList<URL>();
-    
-    private URLClassLoader classLoader = null;
-    
+
+	private final List<URL> list = new ArrayList<URL>();
+
+	private URLClassLoader classLoader = null;
 
 	/**
 	 * The default constructor of this class. During the creation all available libraries will be added to the class loader.
 	 */
 	private PluginClassLoader() {
-        classLoader = AnalysisController.class.getClassLoader();
+		this.classLoader = new URLClassLoader(new URL[]{}, AnalysisController.class.getClassLoader());
 		/* Make sure that all libs are loaded. */
 		final List<MIDependency> libs = FileManager.getInstance().loadAllDependencies();
 		for (final MIDependency lib : libs) {
@@ -82,9 +80,9 @@ public final class PluginClassLoader extends ClassLoader {
 	 *            The URL of the dependency to be added.
 	 */
 	public void addURL(final URL url) {
-        list.add(url);
-        
-        classLoader = new URLClassLoader(list.toArray(new URL[list.size()]), AnalysisController.class.getClassLoader());
+		this.list.add(url);
+
+		this.classLoader = new URLClassLoader(this.list.toArray(new URL[this.list.size()]), AnalysisController.class.getClassLoader());
 	}
 
 	/**
@@ -94,9 +92,9 @@ public final class PluginClassLoader extends ClassLoader {
 	 *            The URL of the dependency to be added.
 	 */
 	public void removeURL(final URL url) {
-		list.remove(url);
-        
-        classLoader = new URLClassLoader(list.toArray(new URL[list.size()]), AnalysisController.class.getClassLoader());
+		this.list.remove(url);
+
+		this.classLoader = new URLClassLoader(this.list.toArray(new URL[this.list.size()]), AnalysisController.class.getClassLoader());
 	}
 
 	/**
@@ -130,6 +128,6 @@ public final class PluginClassLoader extends ClassLoader {
 	 */
 	@Override
 	public Class<?> loadClass(final String name) throws ClassNotFoundException {
-	return	classLoader.loadClass(name);
+		return this.classLoader.loadClass(name);
 	}
 }