1 files changed, 175 insertions, 0 deletions
diff --git a/sca-java-1.x/tags/java-stable-20060304/sca/common/src/main/java/org/apache/tuscany/common/resource/impl/ResourceLoaderImpl.java b/sca-java-1.x/tags/java-stable-20060304/sca/common/src/main/java/org/apache/tuscany/common/resource/impl/ResourceLoaderImpl.java
new file mode 100644
index 0000000000..5f83596f19
--- /dev/null
+++ b/sca-java-1.x/tags/java-stable-20060304/sca/common/src/main/java/org/apache/tuscany/common/resource/impl/ResourceLoaderImpl.java
@@ -0,0 +1,175 @@
+/**
+ *
+ *  Copyright 2005 The Apache Software Foundation or its licensors, as applicable.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License 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 org.apache.tuscany.common.resource.impl;
+
+import java.io.IOException;
+import java.lang.ref.WeakReference;
+import java.net.URL;
+import java.util.Collections;
+import java.util.Enumeration;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Set;
+
+import org.apache.tuscany.common.resource.ResourceLoader;
+
+/**
+ * Default implementation of the ResourceLoader interface.
+ *
+ * @version $Rev: 369102 $ $Date: 2006-01-14 13:48:56 -0800 (Sat, 14 Jan 2006) $
+ */
+public class ResourceLoaderImpl implements ResourceLoader {
+    private final WeakReference<ClassLoader> classLoaderReference;
+    private WeakReference<GeneratedClassLoader> generatedClassLoaderReference;
+    private final List<ResourceLoader> parents;
+
+    /**
+     * A class loader that allows new classes to be defined from an array of bytes
+     */
+    private class GeneratedClassLoader extends ClassLoader {
+        
+        /**
+         * Constructs a new ResourceLoaderImpl.GeneratedClassLoader.
+         */
+        public GeneratedClassLoader(ClassLoader classLoader) {
+            super(classLoader);
+        }
+
+        /**
+         * Converts an array of bytes into a Class.
+         * @param bytes
+         * @return
+         */
+        private Class<?> addClass(byte[] bytes) {
+            return defineClass(null, bytes, 0, bytes.length);
+        }
+        
+    }
+
+    /**
+     * Constructs a new ResourceLoaderImpl.
+     * @param classLoader
+     */
+    public ResourceLoaderImpl(ClassLoader classLoader) {
+        classLoaderReference = new WeakReference(classLoader);
+        generatedClassLoaderReference = new WeakReference(new GeneratedClassLoader(classLoader));
+        ClassLoader parentCL = classLoader.getParent();
+        parents = parentCL == null ? Collections.EMPTY_LIST : Collections.singletonList(new ResourceLoaderImpl(parentCL));
+    }
+
+
+    /**
+     * Return the classloader backing this resource loader.
+     *
+     * @return the classloader that backs this resource loader
+     * @throws IllegalStateException if the classloader has been garbage collected
+     */
+    //FIXME Temporary used to set the classloader on the thread context, need to changed to private 
+    public ClassLoader getClassLoader() throws IllegalStateException {
+        ClassLoader cl = classLoaderReference.get();
+        if (cl == null) {
+            throw new IllegalStateException("Referenced ClassLoader has been garbage collected");
+        }
+        return cl;
+    }
+
+    public List<ResourceLoader> getParents() {
+        return parents;
+    }
+
+    public Class loadClass(String name) throws ClassNotFoundException {
+        GeneratedClassLoader cl = generatedClassLoaderReference.get();
+        if (cl != null) {
+            return Class.forName(name, true, cl);
+        } else {
+            return Class.forName(name, true, getClassLoader());
+        }
+    }
+    
+    public Class<?> addClass(byte[] bytes) {
+        GeneratedClassLoader cl = generatedClassLoaderReference.get();
+        if (cl == null) {
+            cl=new GeneratedClassLoader(getClassLoader());
+            generatedClassLoaderReference = new WeakReference(cl);
+        }
+        return cl.addClass(bytes);
+    }
+
+    public Iterator<URL> getResources(String name) throws IOException {
+        // This implementation used to cache but users are not likely
+        // to ask for the same resource multiple times.
+
+        // Create a new set, add all the resources visible from the current ClassLoader
+        Set<URL> set = new HashSet();
+        ClassLoader classLoader = getClassLoader();
+        for (Enumeration<URL> e = classLoader.getResources(name); e.hasMoreElements();) {
+            set.add(e.nextElement());
+        }
+
+        // Remove the resources visible from the parent ClassLoaders
+        for (ResourceLoader parent : getParents()) {
+            for (Iterator<URL> i = parent.getAllResources(name); i.hasNext();) {
+                set.remove(i.next());
+            }
+        }
+        return set.iterator();
+    }
+
+    public Iterator<URL> getAllResources(String name) throws IOException {
+        return new EnumerationIterator(getClassLoader().getResources(name));
+    }
+
+    public URL getResource(String name) throws IOException {
+        return getClassLoader().getResource(name);
+    }
+
+    public boolean equals(Object obj) {
+        if (obj == this) {
+            return true;
+        }
+        if (!(obj instanceof ResourceLoaderImpl)) {
+            return false;
+        }
+        final ResourceLoaderImpl other = (ResourceLoaderImpl) obj;
+        return getClassLoader() == other.getClassLoader();
+    }
+
+    public int hashCode() {
+        return getClassLoader().hashCode();
+    }
+
+    private static class EnumerationIterator<E> implements Iterator<E> {
+        private final Enumeration<E> e;
+
+        public EnumerationIterator(Enumeration<E> e) {
+            this.e = e;
+        }
+
+        public boolean hasNext() {
+            return e.hasMoreElements();
+        }
+
+        public E next() {
+            return e.nextElement();
+        }
+
+        public void remove() {
+            throw new UnsupportedOperationException();
+        }
+    }
+}