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Diffstat (limited to 'branches/sca-java-2.0-M4/modules/binding-ejb-runtime/src/main/java/org/apache/tuscany/sca/binding/ejb/corba/DynamicStubClassLoader.java')
-rw-r--r-- | branches/sca-java-2.0-M4/modules/binding-ejb-runtime/src/main/java/org/apache/tuscany/sca/binding/ejb/corba/DynamicStubClassLoader.java | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/branches/sca-java-2.0-M4/modules/binding-ejb-runtime/src/main/java/org/apache/tuscany/sca/binding/ejb/corba/DynamicStubClassLoader.java b/branches/sca-java-2.0-M4/modules/binding-ejb-runtime/src/main/java/org/apache/tuscany/sca/binding/ejb/corba/DynamicStubClassLoader.java new file mode 100644 index 0000000000..82554a1c8f --- /dev/null +++ b/branches/sca-java-2.0-M4/modules/binding-ejb-runtime/src/main/java/org/apache/tuscany/sca/binding/ejb/corba/DynamicStubClassLoader.java @@ -0,0 +1,150 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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.sca.binding.ejb.corba; + +import java.lang.reflect.Method; +import java.lang.reflect.Modifier; + +import javax.rmi.CORBA.Stub; + +import net.sf.cglib.core.NamingPolicy; +import net.sf.cglib.core.Predicate; +import net.sf.cglib.proxy.Callback; +import net.sf.cglib.proxy.CallbackFilter; +import net.sf.cglib.proxy.Enhancer; +import net.sf.cglib.proxy.FixedValue; +import net.sf.cglib.proxy.MethodInterceptor; +import net.sf.cglib.proxy.NoOp; + +/** + * @version $Revision$ $Date$ + */ +public class DynamicStubClassLoader extends ClassLoader { + private static final String PACKAGE_PREFIX = "org.omg.stub."; + + @Override + public synchronized Class loadClass(final String name) throws ClassNotFoundException { + ClassLoader classLoader = Thread.currentThread().getContextClassLoader(); + + // check if the stub already exists first + try { + return classLoader.loadClass(name); + } catch (ClassNotFoundException e) { + } + + // if this is not a class from the org.omg.stub name space don't attempt to generate + if (!name.startsWith(PACKAGE_PREFIX)) { + throw new ClassNotFoundException("Could not load class: " + name); + } + + // load the interfaces class we are attempting to create a stub for + Class iface = loadStubInterfaceClass(name, classLoader); + + // create the stub builder + try { + Enhancer enhancer = new Enhancer(); + enhancer.setSuperclass(Stub.class); + enhancer.setInterfaces(new Class[] {iface}); + enhancer.setCallbackFilter(FILTER); + enhancer.setCallbackTypes(new Class[] {NoOp.class, MethodInterceptor.class, FixedValue.class}); + enhancer.setUseFactory(false); + enhancer.setClassLoader(classLoader); + enhancer.setNamingPolicy(new NamingPolicy() { + public String getClassName(String s, String s1, Object o, Predicate predicate) { + return name; + } + }); + + // generate the class + Class result = enhancer.createClass(); + assert result != null; + + StubMethodInterceptor interceptor = new StubMethodInterceptor(iface); + Ids ids = new Ids(iface); + Enhancer.registerStaticCallbacks(result, new Callback[] {NoOp.INSTANCE, interceptor, ids}); + + return result; + } catch (RuntimeException e) { + throw e; + } catch (Error e) { + throw e; + } + } + + private Class loadStubInterfaceClass(String name, ClassLoader classLoader) throws ClassNotFoundException { + try { + int begin = name.lastIndexOf('.') + 1; + String iPackage = name.substring(13, begin); + String iName = iPackage + name.substring(begin + 1, name.length() - 5); + + return classLoader.loadClass(iName); + } catch (ClassNotFoundException e) { + // don't log exceptions from CosNaming because it attempts to load every + // class bound into the name server + + //FIXME this variable is never read, can we remove the + // whole block of code?? + //boolean shouldLog = true; + StackTraceElement[] stackTrace = e.getStackTrace(); + for (int i = 0; i < stackTrace.length; i++) { + StackTraceElement stackTraceElement = stackTrace[i]; + if (stackTraceElement.getClassName().equals("org.omg.CosNaming.NamingContextExtPOA") && stackTraceElement + .getMethodName().equals("_invoke")) { + //shouldLog = false; + break; + } + } + + throw new ClassNotFoundException("Unable to generate stub", e); + } + } + + private static final CallbackFilter FILTER = new CallbackFilter() { + public int accept(Method method) { + // we don't intercept non-public methods like finalize + if (!Modifier.isPublic(method.getModifiers())) { + return 0; + } + + if (method.getReturnType().equals(String[].class) && method.getParameterTypes().length == 0 + && method.getName().equals("_ids")) { + return 2; + } + + if (Modifier.isAbstract(method.getModifiers())) { + return 1; + } + + return 0; + } + }; + + private static final class Ids implements FixedValue { + private final String[] typeIds; + + public Ids(Class type) { + typeIds = Java2IDLUtil.createCorbaIds(type); + } + + public Object loadObject() throws Exception { + return typeIds; + } + } + +} |