diff options
Diffstat (limited to 'sca-java-1.x/tags/java-M1-final/java/sca/common/src/main/java/org/apache/tuscany/common/resource/impl/ResourceLoaderImpl.java')
-rw-r--r-- | sca-java-1.x/tags/java-M1-final/java/sca/common/src/main/java/org/apache/tuscany/common/resource/impl/ResourceLoaderImpl.java | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/sca-java-1.x/tags/java-M1-final/java/sca/common/src/main/java/org/apache/tuscany/common/resource/impl/ResourceLoaderImpl.java b/sca-java-1.x/tags/java-M1-final/java/sca/common/src/main/java/org/apache/tuscany/common/resource/impl/ResourceLoaderImpl.java new file mode 100644 index 0000000000..d306edf3b4 --- /dev/null +++ b/sca-java-1.x/tags/java-M1-final/java/sca/common/src/main/java/org/apache/tuscany/common/resource/impl/ResourceLoaderImpl.java @@ -0,0 +1,137 @@ +/** + * + * 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.Iterator; +import java.util.List; +import java.util.NoSuchElementException; + +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) $ + */ +@SuppressWarnings({"ClassLoader2Instantiation"}) +public class ResourceLoaderImpl implements ResourceLoader { + private final WeakReference<ClassLoader> classLoaderReference; + private WeakReference<GeneratedClassLoader> generatedClassLoaderReference; + private final List<ResourceLoader> parents; + + /** + * Constructs a new ResourceLoaderImpl to wrap a ClassLoader. + * + * @param classLoader the classloader to wrap + */ + public ResourceLoaderImpl(ClassLoader classLoader) { + classLoaderReference = new WeakReference<ClassLoader>(classLoader); + generatedClassLoaderReference = new WeakReference<GeneratedClassLoader>(new GeneratedClassLoader(classLoader)); + ClassLoader parentCL = classLoader.getParent(); + if (null == parentCL) { + parents = Collections.emptyList(); + } else { + parents = Collections.singletonList((ResourceLoader) new ResourceLoaderImpl(parentCL)); + } + } + + + 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<GeneratedClassLoader>(cl); + } + return cl.addClass(bytes); + } + + public Iterator<URL> getResources(String name) throws IOException { + return new EnumerationIterator<URL>(getClassLoader().getResources(name)); + } + + public URL getResource(String name) { + 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() { + // the try/catch is needed here to get IDEA to shut up + // there should be no performance overhead here except when the Exception is thrown + // so I am going to leave it in - feel free to remove if there is any issue + try { + return e.nextElement(); + } catch (NoSuchElementException e1) { + throw e1; + } + } + + public void remove() { + throw new UnsupportedOperationException(); + } + } +} |