Java MethodInterceptor類代碼示例

import org.springframework.cglib.proxy.MethodInterceptor; //導入依賴的package包/類
/**
 * Create a subclass proxy that intercepts calls to getObject(), delegating to the current BeanFactory
 * instead of creating a new instance. These proxies are created only when calling a FactoryBean from
 * within a Bean method, allowing for proper scoping semantics even when working against the FactoryBean
 * instance directly. If a FactoryBean instance is fetched through the container via &-dereferencing,
 * it will not be proxied. This too is aligned with the way XML configuration works.
 */
private Object enhanceFactoryBean(Class<?> fbClass, final ConfigurableBeanFactory beanFactory,
		final String beanName) throws InstantiationException, IllegalAccessException {

	Enhancer enhancer = new Enhancer();
	enhancer.setSuperclass(fbClass);
	enhancer.setUseFactory(false);
	enhancer.setNamingPolicy(SpringNamingPolicy.INSTANCE);
	enhancer.setCallback(new MethodInterceptor() {
		@Override
		public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
			if (method.getName().equals("getObject") && args.length == 0) {
				return beanFactory.getBean(beanName);
			}
			return proxy.invokeSuper(obj, args);
		}
	});
	return enhancer.create();
}
 

import org.springframework.cglib.proxy.MethodInterceptor; //導入依賴的package包/類
@SuppressWarnings("unchecked")
static <T> T wrapWithIfaceImplementation(final Class<T> iface, final Specification<Object> targetSpec) {
   	Enhancer enhancer = new Enhancer();
	enhancer.setInterfaces(new Class[] { iface });
	enhancer.setCallback(new MethodInterceptor() {
           @Override
           public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
           	if ("toString".equals(method.getName())) {
           		return iface.getSimpleName() + "[" + proxy.invoke(targetSpec, args) + "]";
           	}
           	return proxy.invoke(targetSpec, args);
           }
       });
	
	return (T) enhancer.create();
   }
 

import org.springframework.cglib.proxy.MethodInterceptor; //導入依賴的package包/類
@SuppressWarnings("unchecked")
private static <T> T createProxy(final Class<?> classToMock, final MethodInterceptor interceptor) {
	final Enhancer enhancer = new Enhancer();
	enhancer.setSuperclass(classToMock);
	enhancer.setCallbackType(interceptor.getClass());
	final Class<?> proxyClass = enhancer.createClass();
	Enhancer.registerCallbacks(proxyClass, new Callback[] { interceptor });
	return (T) ObjenesisHelper.newInstance(proxyClass);
}
 

import org.springframework.cglib.proxy.MethodInterceptor; //導入依賴的package包/類
public static NamedParameterJdbcOperations wrap(final NamedParameterJdbcOperations jdbcOperations) {
    final Enhancer enhancer = new Enhancer();
    enhancer.setSuperclass(NamedParameterJdbcOperations.class);
    enhancer.setCallback((MethodInterceptor) (obj, method, args, proxy) -> {
        final Stopwatch sw = Stopwatch.createStarted();

        try {
            final String methodName = method.getName();

            if (methodName.startsWith("query")
                    || methodName.startsWith("batchUpdate")
                    || methodName.startsWith("update")) {
                logSqlQuery(args);

                final Object result = method.invoke(jdbcOperations, args);

                if (sw.elapsed(TimeUnit.SECONDS) > 5) {
                    LOG.warn("SQL execution took too long {}", sw);
                }

                return result;
            }

            return method.invoke(jdbcOperations, args);

        } catch (InvocationTargetException e) {
            throw e.getTargetException();
        }
    });

    return (NamedParameterJdbcOperations) enhancer.create();
}
 

import org.springframework.cglib.proxy.MethodInterceptor; //導入依賴的package包/類
@SuppressWarnings("unchecked")
public static <T> T createProxyObject(Class<T> clazz, Interceptor handler) {
    MethodInterceptor methodInterceptor = new ProxyObjectMethodImpl(handler);
    Enhancer enhancer = new Enhancer();
    enhancer.setSuperclass(clazz);
    enhancer.setCallback(methodInterceptor);
    return (T) enhancer.create();
}
 

import org.springframework.cglib.proxy.MethodInterceptor; //導入依賴的package包/類
@Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory context) throws BeansException {
	ClassPathScanningCandidateComponentProvider scanner = new ClassPathScanningCandidateComponentProvider(false) {

		@Override
		protected boolean isCandidateComponent(AnnotatedBeanDefinition beanDefinition) {
			return beanDefinition.getMetadata().isInterface();
		}

	};
	scanner.addIncludeFilter(new AnnotationTypeFilter(Accessor.class));
	for (BeanDefinition bd : scanner.findCandidateComponents(basePackage)) {
		Class<?> accessorCls;
		try {
			accessorCls = Class.forName(bd.getBeanClassName());
		} catch (ClassNotFoundException e) {
			throw new AssertionError(e);
		}
		log.info("Creating proxy accessor: " + accessorCls.getName());
		MethodInterceptor interceptor = new MethodInterceptor() {

			private final Lazy<?> target = new Lazy<>(() -> {
				log.info("Creating actual accessor: " + accessorCls.getName());
				Session session;
				if (AccessorScannerConfigurer.this.session == null)
					session = mainContext.getBean(Session.class);
				else
					session = AccessorScannerConfigurer.this.session;
				MappingManager mappingManager = new MappingManager(session);
				return mappingManager.createAccessor(accessorCls);
			});

			@Override
			public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
				if ("toString".equals(method.getName())) {
					return accessorCls.getName();
				}
				return method.invoke(target.get(), args);
			}

		};
		Enhancer enhancer = new Enhancer();
		enhancer.setInterfaces(new Class<?>[] { accessorCls });
		enhancer.setCallback(interceptor);
		Object bean = enhancer.create();
		String beanName = StringUtils.uncapitalize(accessorCls.getSimpleName());
		context.registerSingleton(beanName, bean);
		log.info("Bean registed, name=" + beanName + ", bean=" + bean.toString());
	}
}
 

import org.springframework.cglib.proxy.MethodInterceptor; //導入依賴的package包/類
@Test
public void asynchronous_publishing() throws InterruptedException {
    final String docId = randomUUID().toString();
    AbstractVersionStoreJdbc<String, String, ?, ?, ?> originalStore = getStore();
    StoreOptions<String, String, ?> options = originalStore.options.toBuilder().publisherType(ASYNC).build();

    /*
     * Override doPublish to block publish until it is verified that inserted version is not returned
     */
    CountDownLatch beforePublish = new CountDownLatch(1);
    CountDownLatch afterPublish = new CountDownLatch(1);
    MethodInterceptor interceptor = (Object o, Method method, Object[] args, MethodProxy methodProxy) -> {
        if (method.getName().equals("publish")) {
            beforePublish.await();
            try {
                return methodProxy.invokeSuper(o, args);
            } finally {
                afterPublish.countDown();
            }
        }
        return methodProxy.invokeSuper(o, args);
    };

    Enhancer enhancer = new Enhancer();
    enhancer.setSuperclass(originalStore.getClass());
    enhancer.setCallback(interceptor);
    VersionStore<String, String> store = (VersionStore<String, String>) enhancer.create(new Class[] { options.getClass() }, new Object[] { options });

    final ObjectVersionGraph<String> originalGraph = ObjectVersionGraph.init(ObjectVersion.<String>builder(rev1).build());
    transactionTemplate.execute(status -> {
        UpdateBatch<String, String> batch = store.updateBatch(docId);
        batch.addVersion(docId, originalGraph.getVersionNode(rev1));
        batch.execute();
        return null;
    });
    // getGraphs(Collection) should not return version before it's published
    GraphResults<String, String> results = store.getGraphs(asList(docId));
    assertThat(results.isEmpty()).isTrue();

    // Publish and verify that published version is found
    beforePublish.countDown();
    afterPublish.await();
    results = store.getGraphs(asList(docId));
    ObjectVersionGraph<String> graph = results.getVersionGraph(docId);
    assertThat(graph.getVersionNode(rev1).getRevision()).isEqualTo(rev1);
}
 

import org.springframework.cglib.proxy.MethodInterceptor; //導入依賴的package包/類
@Test
public void allow_cglib_proxy() {
    final String docId = "docId";
    final Revision revision = new Revision();
    Function<ObjectVersionGraph<String>, Predicate<VersionNode<PropertyPath, Object, String>>> keep = g -> n -> false;

    Map<String, List<Object>> interceptedCalls = new HashMap<>();
    MethodInterceptor interceptor = (Object o, Method method, Object[] args, MethodProxy methodProxy) -> {
        interceptedCalls.put(method.getName(), ImmutableList.copyOf(args));
        return null;
    };

    Enhancer enhancer = new Enhancer();
    enhancer.setSuperclass(getStore().getClass());
    enhancer.setCallback(interceptor);
    @SuppressWarnings("unchecked")
    VersionStore<String, String> store = (VersionStore<String, String>) enhancer.create();

    store.publish();
    assertThat(interceptedCalls.get("publish")).isEqualTo(asList());

    store.reset(docId);
    assertThat(interceptedCalls.get("reset")).isEqualTo(asList(docId));

    store.getOptimizedGraph(docId);
    assertThat(interceptedCalls.get("getOptimizedGraph")).isEqualTo(asList(docId));

    store.getFullGraph(docId);
    assertThat(interceptedCalls.get("getFullGraph")).isEqualTo(asList(docId));

    store.getGraphs(asList(docId));
    assertThat(interceptedCalls.get("getGraphs")).isEqualTo(asList(asList(docId)));

    store.fetchUpdates(docId, revision);
    assertThat(interceptedCalls.get("fetchUpdates")).isEqualTo(asList(docId, revision));

    store.prune(docId, keep);
    assertThat(interceptedCalls.get("prune")).isEqualTo(asList(docId, keep));

    store.optimize(docId, keep);
    assertThat(interceptedCalls.get("optimize")).isEqualTo(asList(docId, keep));

    store.updateBatch(docId);
    assertThat(interceptedCalls.get("updateBatch")).isEqualTo(asList(docId));

    store.updateBatch(asList(docId));
    assertThat(interceptedCalls.get("updateBatch")).isEqualTo(asList(asList(docId)));
}