From 81bb6dcbed53d6edd93d3252e9ac25c3dd267c7c Mon Sep 17 00:00:00 2001 From: rfeng Date: Sat, 24 Oct 2009 04:16:43 +0000 Subject: Add a utility for JDK proxy based lazy instantiation git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@829305 13f79535-47bb-0310-9956-ffa450edef68 --- .../sca/modules/extensibility/META-INF/MANIFEST.MF | 6 +- .../tuscany/sca/extensibility/ServiceHelper.java | 85 ++++++++++++++++++++++ .../sca/extensibility/ServiceHelperTestCase.java | 79 ++++++++++++++++++++ .../tuscany/sca/extensibility/test/Test2Impl.java | 75 ++++++++++++++++++- .../tuscany/sca/extensibility/test/TestImpl.java | 10 ++- .../sca/extensibility/test/TestInterface.java | 5 +- ...he.tuscany.sca.extensibility.test.TestInterface | 2 +- 7 files changed, 253 insertions(+), 9 deletions(-) create mode 100644 java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/ServiceHelperTestCase.java diff --git a/java/sca/modules/extensibility/META-INF/MANIFEST.MF b/java/sca/modules/extensibility/META-INF/MANIFEST.MF index d7729b7ce5..14a9bdb56a 100644 --- a/java/sca/modules/extensibility/META-INF/MANIFEST.MF +++ b/java/sca/modules/extensibility/META-INF/MANIFEST.MF @@ -1,7 +1,6 @@ Manifest-Version: 1.0 Tuscany-Comment1: Export the META-INF.services under an "internal" attribute - so that it can be seen only by the bundle itself without following the - DynamicImport-Package * + so that it can be seen only by the bundle itself without following the DynamicImport-Package * Export-Package: org.apache.tuscany.sca.core;version="2.0.0"; uses:="org.apache.tuscany.sca.extensibility", org.apache.tuscany.sca.extensibility;version="2.0.0" @@ -14,7 +13,8 @@ Bnd-LastModified: 1225397079296 Bundle-ManifestVersion: 2 Bundle-License: http://www.apache.org/licenses/LICENSE-2.0.txt Bundle-Description: Apache Tuscany SCA Extensibility -Import-Package: org.apache.tuscany.sca.core;version="2.0.0", +Import-Package: javax.xml.namespace, + org.apache.tuscany.sca.core;version="2.0.0", org.apache.tuscany.sca.extensibility;version="2.0.0" Bundle-SymbolicName: org.apache.tuscany.sca.extensibility Bundle-DocURL: http://www.apache.org/ diff --git a/java/sca/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceHelper.java b/java/sca/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceHelper.java index c642667f77..975a7692ab 100644 --- a/java/sca/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceHelper.java +++ b/java/sca/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceHelper.java @@ -20,6 +20,9 @@ package org.apache.tuscany.sca.extensibility; import java.lang.reflect.Constructor; +import java.lang.reflect.InvocationHandler; +import java.lang.reflect.Method; +import java.lang.reflect.Proxy; import java.util.Collection; import java.util.Map; @@ -137,4 +140,86 @@ public class ServiceHelper { return instance; } + public static T newLazyInstance(ExtensionPointRegistry registry, ServiceDeclaration sd, Class serviceType) { + return serviceType.cast(Proxy.newProxyInstance(serviceType.getClassLoader(), + new Class[] {serviceType, LifeCycleListener.class}, + new InvocationHandlerImpl(registry, serviceType, sd))); + } + + private static class InvocationHandlerImpl implements InvocationHandler { + private ExtensionPointRegistry registry; + private Class type; + private ServiceDeclaration sd; + private Object instance; + + private final static Method STOP_METHOD = getMethod(LifeCycleListener.class, "stop"); + private final static Method START_METHOD = getMethod(LifeCycleListener.class, "start"); + private final static Method EQUALS_METHOD = getMethod(Object.class, "equals"); + private final static Method HASHCODE_METHOD = getMethod(Object.class, "hashCode"); + private final static Method TOSTRING_METHOD = getMethod(Object.class, "toString"); + + private static Method getMethod(Class type, String name) { + Method[] methods = type.getMethods(); + for (Method method : methods) { + if (name.equals(method.getName())) { + return method; + } + } + return null; + } + + public InvocationHandlerImpl(ExtensionPointRegistry registry, Class type, ServiceDeclaration sd) { + super(); + this.registry = registry; + this.sd = sd; + this.type = type; + } + + private Object getAttribute(Method method) throws Exception { + if (method.getParameterTypes().length != 0) { + return null; + } + String name = method.getName(); + if (name.equals("getModelType") && method.getReturnType() == Class.class) { + return sd.loadClass(sd.getAttributes().get("model")); + } else if (name.equals("getArtifactType")) { + return ServiceDeclarationParser.getQName(sd.getAttributes().get("qname")); + } + return null; + } + + public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { + synchronized (this) { + // Check if the method is to get the qname/model attribute + Object value = getAttribute(method); + if (value != null) { + return value; + } + if (instance == null && method.getDeclaringClass() == type) { + // Only initialize the instance when a method on the service type is invoked + instance = newInstance(registry, sd); + start(instance); + } + if (method.equals(EQUALS_METHOD)) { + return proxy == args[0]; + } else if (method.equals(HASHCODE_METHOD)) { + return System.identityHashCode(proxy); + } else if (method.equals(TOSTRING_METHOD)) { + return "Proxy: " + sd.toString(); + } + if (instance == null) { + return null; + } + } + if (method.equals(STOP_METHOD)) { + stop(instance); + return null; + } else if (method.equals(START_METHOD)) { + // Skip the start() + return null; + } else { + return method.invoke(instance, args); + } + } + } } diff --git a/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/ServiceHelperTestCase.java b/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/ServiceHelperTestCase.java new file mode 100644 index 0000000000..7920fdf4f4 --- /dev/null +++ b/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/ServiceHelperTestCase.java @@ -0,0 +1,79 @@ +/* + * 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.extensibility; + +import java.lang.reflect.Proxy; +import java.util.Collection; +import java.util.Iterator; + +import javax.xml.namespace.QName; + +import org.apache.tuscany.sca.core.DefaultExtensionPointRegistry; +import org.apache.tuscany.sca.core.ExtensionPointRegistry; +import org.apache.tuscany.sca.core.LifeCycleListener; +import org.apache.tuscany.sca.extensibility.test.Test2Impl; +import org.apache.tuscany.sca.extensibility.test.TestImpl; +import org.apache.tuscany.sca.extensibility.test.TestInterface; +import org.junit.Assert; +import org.junit.Test; + +public class ServiceHelperTestCase { + @Test + public void testNewInstance() throws Exception { + Test2Impl implA = ServiceHelper.newInstance(Test2Impl.class); + Assert.assertNull(implA.getRegistry()); + + TestImpl impl1 = ServiceHelper.newInstance(TestImpl.class); + Assert.assertNotNull(impl1); + } + + @Test + public void testNewInstance2() throws Exception { + Collection sds = + ServiceDiscovery.getInstance().getServiceDeclarations(TestInterface.class, true); + ExtensionPointRegistry registry = new DefaultExtensionPointRegistry(); + Iterator iterator = sds.iterator(); + Test2Impl implA = ServiceHelper.newInstance(registry, iterator.next()); + Assert.assertSame(registry, implA.getRegistry()); + + TestImpl impl1 = ServiceHelper.newInstance(registry, iterator.next()); + Assert.assertNotNull(impl1); + } + + @Test + public void testNewLazyInstance() throws Exception { + Collection sds = + ServiceDiscovery.getInstance().getServiceDeclarations(TestInterface.class, true); + ExtensionPointRegistry registry = new DefaultExtensionPointRegistry(); + Iterator iterator = sds.iterator(); + TestInterface ti = ServiceHelper.newLazyInstance(registry, iterator.next(), TestInterface.class); + Assert.assertTrue(Proxy.isProxyClass(ti.getClass())); + Assert.assertTrue(ti instanceof LifeCycleListener); + Assert.assertTrue(ti.toString().startsWith("Proxy")); + Assert.assertEquals(System.identityHashCode(ti), ti.hashCode()); + ServiceHelper.start(ti); + ServiceHelper.stop(ti); + QName name = ti.getArtifactType(); + Assert.assertEquals(new QName("http://sample", "Test2"), name); + String str = ti.test("ABC"); + Assert.assertEquals("Test 2: ABC", str); + ServiceHelper.stop(ti); + } +} diff --git a/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/Test2Impl.java b/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/Test2Impl.java index 49bc0d022e..6a1ba4d7ba 100644 --- a/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/Test2Impl.java +++ b/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/Test2Impl.java @@ -19,16 +19,85 @@ package org.apache.tuscany.sca.extensibility.test; +import javax.xml.namespace.QName; + +import org.apache.tuscany.sca.core.ExtensionPointRegistry; +import org.apache.tuscany.sca.core.LifeCycleListener; + /** * */ -public class Test2Impl implements TestInterface { +public class Test2Impl implements TestInterface, LifeCycleListener { + private ExtensionPointRegistry registry; + public int state = 0; + + public Test2Impl(ExtensionPointRegistry registry) { + this.registry = registry; + } + + public Test2Impl() { + } - /* (non-Javadoc) + /** * @see org.apache.tuscany.sca.extensibility.test.TestInterface#test(java.lang.String) */ - public void test(String str) { + public String test(String str) { System.out.println("Test 2: " + str); + return "Test 2: " + str; + } + + public ExtensionPointRegistry getRegistry() { + return registry; + } + + public void start() { + state = 1; + } + + public void stop() { + state = -1; + } + + public int getState() { + return state; + } + + @Override + public int hashCode() { + final int prime = 31; + int result = 1; + result = prime * result + ((registry == null) ? 0 : registry.hashCode()); + result = prime * result + state; + return result; + } + + @Override + public boolean equals(Object obj) { + if (this == obj) + return true; + if (obj == null) + return false; + if (getClass() != obj.getClass()) + return false; + Test2Impl other = (Test2Impl)obj; + if (registry == null) { + if (other.registry != null) + return false; + } else if (!registry.equals(other.registry)) + return false; + if (state != other.state) + return false; + return true; + } + + @Override + public String toString() { + return "Test2Impl [state=" + state + "]"; + } + + public QName getArtifactType() { + // TODO Auto-generated method stub + return new QName("http://sample", "Test2"); } } diff --git a/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/TestImpl.java b/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/TestImpl.java index c925bf07c0..4def8a5227 100644 --- a/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/TestImpl.java +++ b/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/TestImpl.java @@ -19,6 +19,8 @@ package org.apache.tuscany.sca.extensibility.test; +import javax.xml.namespace.QName; + /** * */ @@ -27,8 +29,14 @@ public class TestImpl implements TestInterface { /* (non-Javadoc) * @see org.apache.tuscany.sca.extensibility.test.TestInterface#test(java.lang.String) */ - public void test(String str) { + public String test(String str) { System.out.println("Test: " + str); + return "Test: " + str; + } + + public QName getArtifactType() { + // TODO Auto-generated method stub + return null; } } diff --git a/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/TestInterface.java b/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/TestInterface.java index a1897d86c0..2f0c34df7d 100644 --- a/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/TestInterface.java +++ b/java/sca/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/test/TestInterface.java @@ -19,9 +19,12 @@ package org.apache.tuscany.sca.extensibility.test; +import javax.xml.namespace.QName; + /** * */ public interface TestInterface { - void test(String str); + String test(String str); + QName getArtifactType(); } diff --git a/java/sca/modules/extensibility/src/test/resources/META-INF/services/org.apache.tuscany.sca.extensibility.test.TestInterface b/java/sca/modules/extensibility/src/test/resources/META-INF/services/org.apache.tuscany.sca.extensibility.test.TestInterface index 25cd732a27..12991071e5 100644 --- a/java/sca/modules/extensibility/src/test/resources/META-INF/services/org.apache.tuscany.sca.extensibility.test.TestInterface +++ b/java/sca/modules/extensibility/src/test/resources/META-INF/services/org.apache.tuscany.sca.extensibility.test.TestInterface @@ -15,5 +15,5 @@ # specific language governing permissions and limitations # under the License. org.apache.tuscany.sca.extensibility.test.TestImpl;ranking=10;attr=123 -org.apache.tuscany.sca.extensibility.test.Test2Impl;ranking=20;attr=abc +org.apache.tuscany.sca.extensibility.test.Test2Impl;ranking=20,attr=abc,qname=http://sample#Test2,model=org.apache.tuscany.sca.extensibility.test.TestInterface org.apache.tuscany.sca.extensibility.test.DummyImpl \ No newline at end of file -- cgit v1.2.3