From 5ddf0de8b6ecb45f2420c9b2e68f82cb7c52dfbb Mon Sep 17 00:00:00 2001
From: Erik Brakkee
Date: Sat, 31 Jul 2010 22:43:03 +0000
Subject: [PATCH]
---
.../SerializableInvocationHandler.java | 77 ++++++++++++
.../general/SerializableProxyFactory.java | 113 ++++++++++++++++++
.../general/ThreadSpecificProxyFactory.java | 5 +
.../general/SerializableProxyFactoryTest.java | 94 +++++++++++++++
4 files changed, 289 insertions(+)
create mode 100644 support/general/src/main/java/org/wamblee/general/SerializableInvocationHandler.java
create mode 100644 support/general/src/main/java/org/wamblee/general/SerializableProxyFactory.java
create mode 100644 support/general/src/test/java/org/wamblee/general/SerializableProxyFactoryTest.java
diff --git a/support/general/src/main/java/org/wamblee/general/SerializableInvocationHandler.java b/support/general/src/main/java/org/wamblee/general/SerializableInvocationHandler.java
new file mode 100644
index 00000000..51704b06
--- /dev/null
+++ b/support/general/src/main/java/org/wamblee/general/SerializableInvocationHandler.java
@@ -0,0 +1,77 @@
+/*
+ * Copyright 2005-2010 the original author or authors.
+ *
+ * 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.wamblee.general;
+
+import java.io.Serializable;
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * Serialiable invocation handler that delegate to a possibly non-serializable object.
+ * The trick is to store the object in a static map with a unique id and use the id to
+ * retrieve the object instead of storing the object.
+ *
+ * @author Erik Brakkee
+ *
+ * @param
+ */
+class SerializableInvocationHandler implements InvocationHandler,
+ Serializable {
+
+ /**
+ * We store a map of unique ids of invocation handlers to thread local
+ * storage of the service. In this way, serialiability of the generated
+ * proxy is obtained (required by framweorks such as wicket). Also,
+ * different factories will still be separate and never use the same
+ * threadlocal storage.
+ */
+ private static Map STORAGE = new ConcurrentHashMap();
+
+ private static AtomicInteger COUNTER = new AtomicInteger();
+
+ private int id;
+ private Class clazz;
+
+ /**
+ * Constructs the handler.
+ *
+ * @param aSvc
+ * Thread local for the service.
+ * @param aClass
+ * Service interface class.
+ */
+ public SerializableInvocationHandler(T aSvc, Class aClass) {
+ id = COUNTER.incrementAndGet();
+ clazz = aClass;
+ STORAGE.put(id, aSvc);
+ }
+
+ @Override
+ public Object invoke(Object aProxy, Method aMethod, Object[] aArgs)
+ throws Throwable {
+
+ T local = (T)STORAGE.get(id);
+ try {
+ return aMethod.invoke(local, aArgs);
+ } catch (InvocationTargetException e) {
+ throw e.getCause();
+ }
+ }
+}
\ No newline at end of file
diff --git a/support/general/src/main/java/org/wamblee/general/SerializableProxyFactory.java b/support/general/src/main/java/org/wamblee/general/SerializableProxyFactory.java
new file mode 100644
index 00000000..34b7e3a5
--- /dev/null
+++ b/support/general/src/main/java/org/wamblee/general/SerializableProxyFactory.java
@@ -0,0 +1,113 @@
+/*
+ * Copyright 2005-2010 the original author or authors.
+ *
+ * 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.wamblee.general;
+
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Proxy;
+
+/**
+ *
+ * Serializable proxy factory that allows to create serializable proxies to
+ * objects that are themselves not serializable.
+ *
+ *
+ *
+ * This class does not do any cleanup so it is recommended to only use this in
+ * test utilities.
+ *
+ *
+ *
+ * @author Erik Brakkee
+ *
+ * @param
+ */
+public class SerializableProxyFactory {
+
+ private T svc;
+ private Class clazz;
+ private T proxy;
+
+ /**
+ * Constructs the factory.
+ *
+ * @param aClass
+ * Interface class of the service to proxy.
+ */
+ public SerializableProxyFactory(Class aClass) {
+ this(aClass, null);
+ }
+
+ /**
+ * Constructs the factory with a callback to create thread-specific objects
+ * automatically.
+ *
+ * @param aClass
+ * Interface class of the service to proxy.
+ * @param aCallback
+ * Callback to create the object if it does not exist. When null,
+ * then no initialization is done.
+ */
+ public SerializableProxyFactory(Class aClass, T aSvc) {
+ if (!aClass.isInterface()) {
+ throw new IllegalArgumentException("Class " + aClass.getName() +
+ " is not an interface");
+ }
+ if (!aClass.isInstance(aSvc)) {
+ throw new IllegalArgumentException("Object " + aSvc +
+ " cannot be cast to " + aSvc.getClass());
+ }
+ svc = aSvc;
+ clazz = aClass;
+ proxy = createProxy();
+
+ }
+
+ /**
+ * Gets the underlying service.
+ *
+ * @return Service.
+ */
+ public T get() {
+ return svc;
+ }
+
+ /**
+ * Gets the proxy that delegates to the thread-specific instance set by
+ * {@link #set(Object)}
+ *
+ * @return Proxy.
+ */
+ public T getProxy() {
+ return proxy;
+ }
+
+ private T createProxy() {
+ InvocationHandler handler = new SerializableInvocationHandler(svc,
+ clazz);
+ Class proxyClass = Proxy.getProxyClass(clazz.getClassLoader(),
+ new Class[] { clazz });
+ T proxyObj;
+ try {
+ proxyObj = (T) proxyClass.getConstructor(
+ new Class[] { InvocationHandler.class }).newInstance(
+ new Object[] { handler });
+ return proxyObj;
+ } catch (Exception e) {
+ throw new RuntimeException("Could not create proxy for " +
+ clazz.getName(), e);
+ }
+ }
+}
diff --git a/support/general/src/main/java/org/wamblee/general/ThreadSpecificProxyFactory.java b/support/general/src/main/java/org/wamblee/general/ThreadSpecificProxyFactory.java
index db51ba1c..ac1ec8fc 100644
--- a/support/general/src/main/java/org/wamblee/general/ThreadSpecificProxyFactory.java
+++ b/support/general/src/main/java/org/wamblee/general/ThreadSpecificProxyFactory.java
@@ -48,6 +48,11 @@ import java.lang.reflect.Proxy;
* distributed context where it can be sent to another JVM.
*
*
+ *
+ * This class currently does not do any cleanup. So it should not be used in production code
+ * but only in test utilities.
+ *
+ *
* @param T
* Interface to proxy.
* @author Erik Brakkee
diff --git a/support/general/src/test/java/org/wamblee/general/SerializableProxyFactoryTest.java b/support/general/src/test/java/org/wamblee/general/SerializableProxyFactoryTest.java
new file mode 100644
index 00000000..5ff74768
--- /dev/null
+++ b/support/general/src/test/java/org/wamblee/general/SerializableProxyFactoryTest.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright 2005-2010 the original author or authors.
+ *
+ * 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.wamblee.general;
+
+import static org.mockito.Mockito.*;
+
+import org.apache.derby.impl.sql.execute.OnceResultSet;
+import org.junit.Before;
+import org.junit.Test;
+
+public class SerializableProxyFactoryTest {
+
+ public static interface MyInterface {
+ void doSomething();
+ }
+
+ private MyInterface intf;
+
+ @Before
+ public void setUp() {
+ intf = mock(MyInterface.class);
+ }
+
+ @Test
+ public void testProxyWorks() {
+ SerializableProxyFactory factory = new SerializableProxyFactory(
+ MyInterface.class, intf);
+ MyInterface proxy = factory.getProxy();
+ proxy.doSomething();
+ verify(intf).doSomething();
+ }
+
+ @Test
+ public void testProxiesAreUnique() {
+ SerializableProxyFactory factory1 = new SerializableProxyFactory(
+ MyInterface.class, intf);
+ MyInterface proxy1 = factory1.getProxy();
+
+ MyInterface intf2 = mock(MyInterface.class);
+ SerializableProxyFactory factory2 = new SerializableProxyFactory(
+ MyInterface.class, intf2);
+ MyInterface proxy2 = factory2.getProxy();
+
+ proxy1.doSomething();
+ verify(intf, times(1)).doSomething();
+ verifyNoMoreInteractions(intf);
+ verifyNoMoreInteractions(intf2);
+
+ reset(intf);
+ reset(intf2);
+
+ proxy2.doSomething();
+ verify(intf2, times(1)).doSomething();
+ verifyNoMoreInteractions(intf);
+ verifyNoMoreInteractions(intf2);
+ }
+
+ @Test
+ public void testStillWorksAfterSerialization() throws Exception {
+ SerializableProxyFactory factory = new SerializableProxyFactory(
+ MyInterface.class, intf);
+ MyInterface proxy = factory.getProxy();
+
+ MyInterface deserialized = ObjectSerializationUtils.deserialize(
+ ObjectSerializationUtils.serialize(proxy), MyInterface.class);
+ deserialized.doSomething();
+ verify(intf).doSomething();
+ }
+
+ @Test(expected = IllegalArgumentException.class)
+ public void testWrongServiceType() {
+ SerializableProxyFactory factory = new SerializableProxyFactory(
+ MyInterface.class, "hello");
+ }
+
+ @Test(expected = IllegalArgumentException.class)
+ public void testNotAnInterface() {
+ SerializableProxyFactory factory = new SerializableProxyFactory(
+ String.class, "hello");
+ }
+}
--
2.31.1