| /** |
| * Copyright (C) 2009 Google Inc. |
| * |
| * 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 com.google.inject.struts2; |
| |
| import java.lang.annotation.Annotation; |
| import java.util.ArrayList; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.logging.Logger; |
| |
| import com.google.inject.AbstractModule; |
| import com.google.inject.Binder; |
| import com.google.inject.Injector; |
| import com.google.inject.internal.Annotations; |
| import com.opensymphony.xwork2.ActionInvocation; |
| import com.opensymphony.xwork2.ObjectFactory; |
| import com.opensymphony.xwork2.config.ConfigurationException; |
| import com.opensymphony.xwork2.config.entities.InterceptorConfig; |
| import com.opensymphony.xwork2.inject.Inject; |
| import com.opensymphony.xwork2.interceptor.Interceptor; |
| |
| /** |
| * Cleanup up version from Bob's GuiceObjectFactory. Now works properly with |
| * GS2 and fixes several bugs. |
| * |
| * @author dhanji@gmail.com |
| * @author benmccann.com |
| */ |
| public class Struts2Factory extends ObjectFactory { |
| |
| private static final long serialVersionUID = 1L; |
| private static final Logger logger = Logger.getLogger(Struts2Factory.class.getName()); |
| private static final String ERROR_NO_INJECTOR = |
| "Cannot find a Guice injector. Are you sure you registered a GuiceServletContextListener " |
| + "that uses the Struts2GuicePluginModule in your application's web.xml?"; |
| |
| private static @com.google.inject.Inject Injector injector; |
| |
| private final List<ProvidedInterceptor> interceptors = new ArrayList<ProvidedInterceptor>(); |
| private volatile Injector strutsInjector; |
| |
| @Override |
| public boolean isNoArgConstructorRequired() { |
| return false; |
| } |
| |
| @Inject(value = "guice.module", required = false) |
| void setModule(String moduleClassName) { |
| throw new RuntimeException("The struts2 plugin no longer supports" |
| + " specifying a module via the 'guice.module' property in XML." |
| + " Please install your module via a GuiceServletContextListener instead."); |
| } |
| |
| Set<Class<?>> boundClasses = new HashSet<Class<?>>(); |
| |
| public Class<?> getClassInstance(String name) throws ClassNotFoundException { |
| Class<?> clazz = super.getClassInstance(name); |
| |
| synchronized (this) { |
| if (strutsInjector == null) { |
| // We can only bind each class once. |
| if (!boundClasses.contains(clazz)) { |
| try { |
| // Calling these methods now helps us detect ClassNotFoundErrors |
| // early. |
| clazz.getDeclaredFields(); |
| clazz.getDeclaredMethods(); |
| |
| boundClasses.add(clazz); |
| } catch (Throwable t) { |
| // Struts should still work even though some classes aren't in the |
| // classpath. It appears we always get the exception here when |
| // this is the case. |
| return clazz; |
| } |
| } |
| } |
| } |
| |
| return clazz; |
| } |
| |
| @Override @SuppressWarnings("unchecked") |
| public Object buildBean(Class clazz, Map<String, Object> extraContext) { |
| if (strutsInjector == null) { |
| synchronized (this) { |
| if (strutsInjector == null) { |
| createInjector(); |
| } |
| } |
| } |
| return strutsInjector.getInstance(clazz); |
| } |
| |
| private void createInjector() { |
| logger.info("Loading struts2 Guice support..."); |
| |
| // Something is wrong, since this should be there if GuiceServletContextListener |
| // was present. |
| if (injector == null) { |
| logger.severe(ERROR_NO_INJECTOR); |
| throw new RuntimeException(ERROR_NO_INJECTOR); |
| } |
| |
| this.strutsInjector = injector.createChildInjector(new AbstractModule() { |
| protected void configure() { |
| |
| // Tell the injector about all the action classes, etc., so it |
| // can validate them at startup. |
| for (Class<?> boundClass : boundClasses) { |
| // TODO: Set source from Struts XML. |
| bind(boundClass); |
| } |
| |
| // Validate the interceptor class. |
| for (ProvidedInterceptor interceptor : interceptors) { |
| interceptor.validate(binder()); |
| } |
| } |
| }); |
| |
| // Inject interceptors. |
| for (ProvidedInterceptor interceptor : interceptors) { |
| interceptor.inject(); |
| } |
| |
| logger.info("Injector created successfully."); |
| } |
| |
| @SuppressWarnings("unchecked") |
| public Interceptor buildInterceptor(InterceptorConfig interceptorConfig, |
| Map interceptorRefParams) throws ConfigurationException { |
| // Ensure the interceptor class is present. |
| Class<? extends Interceptor> interceptorClass; |
| try { |
| interceptorClass = (Class<? extends Interceptor>) |
| getClassInstance(interceptorConfig.getClassName()); |
| } catch (ClassNotFoundException e) { |
| throw new RuntimeException(e); |
| } |
| |
| ProvidedInterceptor providedInterceptor = new ProvidedInterceptor( |
| interceptorConfig, interceptorRefParams, interceptorClass); |
| interceptors.add(providedInterceptor); |
| return providedInterceptor; |
| } |
| |
| private Interceptor superBuildInterceptor(InterceptorConfig interceptorConfig, |
| Map<String, String> interceptorRefParams) throws ConfigurationException { |
| return super.buildInterceptor(interceptorConfig, interceptorRefParams); |
| } |
| |
| private class ProvidedInterceptor implements Interceptor { |
| |
| private static final long serialVersionUID = 1L; |
| |
| private final InterceptorConfig config; |
| private final Map<String, String> params; |
| private final Class<? extends Interceptor> interceptorClass; |
| private Interceptor delegate; |
| |
| ProvidedInterceptor(InterceptorConfig config, Map<String, String> params, |
| Class<? extends Interceptor> interceptorClass) { |
| this.config = config; |
| this.params = params; |
| this.interceptorClass = interceptorClass; |
| } |
| |
| void validate(Binder binder) { |
| // TODO: Set source from Struts XML. |
| if (hasScope(interceptorClass)) { |
| binder.addError("Scoping interceptors is not currently supported." |
| + " Please remove the scope annotation from " |
| + interceptorClass.getName() + "."); |
| } |
| |
| // Make sure it implements Interceptor. |
| if (!Interceptor.class.isAssignableFrom(interceptorClass)) { |
| binder.addError(interceptorClass.getName() + " must implement " |
| + Interceptor.class.getName() + "."); |
| } |
| } |
| |
| void inject() { |
| delegate = superBuildInterceptor(config, params); |
| } |
| |
| public void destroy() { |
| if (null != delegate) { |
| delegate.destroy(); |
| } |
| } |
| |
| public void init() { |
| throw new AssertionError(); |
| } |
| |
| public String intercept(ActionInvocation invocation) throws Exception { |
| return delegate.intercept(invocation); |
| } |
| } |
| |
| /** |
| * Returns true if the given class has a scope annotation. |
| */ |
| private static boolean hasScope(Class<? extends Interceptor> interceptorClass) { |
| for (Annotation annotation : interceptorClass.getAnnotations()) { |
| if (Annotations.isScopeAnnotation(annotation.annotationType())) { |
| return true; |
| } |
| } |
| return false; |
| } |
| } |