Java tutorial
/* * Copyright 2002-2018 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.springframework.test.context.web; import javax.servlet.ServletContext; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.factory.support.DefaultListableBeanFactory; import org.springframework.context.ApplicationContext; import org.springframework.context.ConfigurableApplicationContext; import org.springframework.context.annotation.AnnotationConfigUtils; import org.springframework.core.io.DefaultResourceLoader; import org.springframework.core.io.FileSystemResourceLoader; import org.springframework.core.io.ResourceLoader; import org.springframework.mock.web.MockServletContext; import org.springframework.test.context.MergedContextConfiguration; import org.springframework.test.context.support.AbstractContextLoader; import org.springframework.util.Assert; import org.springframework.web.context.WebApplicationContext; import org.springframework.web.context.support.GenericWebApplicationContext; /** * Abstract, generic extension of {@link AbstractContextLoader} that loads a * {@link GenericWebApplicationContext}. * * <p>If instances of concrete subclasses are invoked via the * {@link org.springframework.test.context.SmartContextLoader SmartContextLoader} * SPI, the context will be loaded from the {@link MergedContextConfiguration} * provided to {@link #loadContext(MergedContextConfiguration)}. In such cases, a * {@code SmartContextLoader} will decide whether to load the context from * <em>locations</em> or <em>annotated classes</em>. Note that {@code * AbstractGenericWebContextLoader} does not support the {@code * loadContext(String... locations)} method from the legacy * {@link org.springframework.test.context.ContextLoader ContextLoader} SPI. * * <p>Concrete subclasses must provide an appropriate implementation of * {@link #loadBeanDefinitions}. * * @author Sam Brannen * @author Phillip Webb * @since 3.2 * @see #loadContext(MergedContextConfiguration) * @see #loadContext(String...) */ public abstract class AbstractGenericWebContextLoader extends AbstractContextLoader { protected static final Log logger = LogFactory.getLog(AbstractGenericWebContextLoader.class); // SmartContextLoader /** * Load a Spring {@link WebApplicationContext} from the supplied * {@link MergedContextConfiguration}. * <p>Implementation details: * <ul> * <li>Calls {@link #validateMergedContextConfiguration(WebMergedContextConfiguration)} * to allow subclasses to validate the supplied configuration before proceeding.</li> * <li>Creates a {@link GenericWebApplicationContext} instance.</li> * <li>If the supplied {@code MergedContextConfiguration} references a * {@linkplain MergedContextConfiguration#getParent() parent configuration}, * the corresponding {@link MergedContextConfiguration#getParentApplicationContext() * ApplicationContext} will be retrieved and * {@linkplain GenericWebApplicationContext#setParent(ApplicationContext) set as the parent} * for the context created by this method.</li> * <li>Delegates to {@link #configureWebResources} to create the * {@link MockServletContext} and set it in the {@code WebApplicationContext}.</li> * <li>Calls {@link #prepareContext} to allow for customizing the context * before bean definitions are loaded.</li> * <li>Calls {@link #customizeBeanFactory} to allow for customizing the * context's {@code DefaultListableBeanFactory}.</li> * <li>Delegates to {@link #loadBeanDefinitions} to populate the context * from the locations or classes in the supplied {@code MergedContextConfiguration}.</li> * <li>Delegates to {@link AnnotationConfigUtils} for * {@linkplain AnnotationConfigUtils#registerAnnotationConfigProcessors registering} * annotation configuration processors.</li> * <li>Calls {@link #customizeContext} to allow for customizing the context * before it is refreshed.</li> * <li>{@link ConfigurableApplicationContext#refresh Refreshes} the * context and registers a JVM shutdown hook for it.</li> * </ul> * @return a new web application context * @see org.springframework.test.context.SmartContextLoader#loadContext(MergedContextConfiguration) * @see GenericWebApplicationContext */ @Override public final ConfigurableApplicationContext loadContext(MergedContextConfiguration mergedConfig) throws Exception { Assert.isTrue(mergedConfig instanceof WebMergedContextConfiguration, () -> String .format("Cannot load WebApplicationContext from non-web merged context configuration %s. " + "Consider annotating your test class with @WebAppConfiguration.", mergedConfig)); WebMergedContextConfiguration webMergedConfig = (WebMergedContextConfiguration) mergedConfig; if (logger.isDebugEnabled()) { logger.debug(String.format("Loading WebApplicationContext for merged context configuration %s.", webMergedConfig)); } validateMergedContextConfiguration(webMergedConfig); GenericWebApplicationContext context = new GenericWebApplicationContext(); ApplicationContext parent = mergedConfig.getParentApplicationContext(); if (parent != null) { context.setParent(parent); } configureWebResources(context, webMergedConfig); prepareContext(context, webMergedConfig); customizeBeanFactory(context.getDefaultListableBeanFactory(), webMergedConfig); loadBeanDefinitions(context, webMergedConfig); AnnotationConfigUtils.registerAnnotationConfigProcessors(context); customizeContext(context, webMergedConfig); context.refresh(); context.registerShutdownHook(); return context; } /** * Validate the supplied {@link WebMergedContextConfiguration} with respect to * what this context loader supports. * <p>The default implementation is a <em>no-op</em> but can be overridden by * subclasses as appropriate. * @param mergedConfig the merged configuration to validate * @throws IllegalStateException if the supplied configuration is not valid * for this context loader * @since 4.0.4 */ protected void validateMergedContextConfiguration(WebMergedContextConfiguration mergedConfig) { /* no-op */ } /** * Configures web resources for the supplied web application context (WAC). * <h4>Implementation Details</h4> * <p>If the supplied WAC has no parent or its parent is not a WAC, the * supplied WAC will be configured as the Root WAC (see "<em>Root WAC * Configuration</em>" below). * <p>Otherwise the context hierarchy of the supplied WAC will be traversed * to find the top-most WAC (i.e., the root); and the {@link ServletContext} * of the Root WAC will be set as the {@code ServletContext} for the supplied * WAC. * <h4>Root WAC Configuration</h4> * <ul> * <li>The resource base path is retrieved from the supplied * {@code WebMergedContextConfiguration}.</li> * <li>A {@link ResourceLoader} is instantiated for the {@link MockServletContext}: * if the resource base path is prefixed with "{@code classpath:}", a * {@link DefaultResourceLoader} will be used; otherwise, a * {@link FileSystemResourceLoader} will be used.</li> * <li>A {@code MockServletContext} will be created using the resource base * path and resource loader.</li> * <li>The supplied {@link GenericWebApplicationContext} is then stored in * the {@code MockServletContext} under the * {@link WebApplicationContext#ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE} key.</li> * <li>Finally, the {@code MockServletContext} is set in the * {@code WebApplicationContext}.</li> * @param context the web application context for which to configure the web resources * @param webMergedConfig the merged context configuration to use to load the web application context */ protected void configureWebResources(GenericWebApplicationContext context, WebMergedContextConfiguration webMergedConfig) { ApplicationContext parent = context.getParent(); // If the WebApplicationContext has no parent or the parent is not a WebApplicationContext, // set the current context as the root WebApplicationContext: if (parent == null || (!(parent instanceof WebApplicationContext))) { String resourceBasePath = webMergedConfig.getResourceBasePath(); ResourceLoader resourceLoader = (resourceBasePath.startsWith(ResourceLoader.CLASSPATH_URL_PREFIX) ? new DefaultResourceLoader() : new FileSystemResourceLoader()); ServletContext servletContext = new MockServletContext(resourceBasePath, resourceLoader); servletContext.setAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE, context); context.setServletContext(servletContext); } else { ServletContext servletContext = null; // Find the root WebApplicationContext while (parent != null) { if (parent instanceof WebApplicationContext && !(parent.getParent() instanceof WebApplicationContext)) { servletContext = ((WebApplicationContext) parent).getServletContext(); break; } parent = parent.getParent(); } Assert.state(servletContext != null, "Failed to find root WebApplicationContext in the context hierarchy"); context.setServletContext(servletContext); } } /** * Customize the internal bean factory of the {@code WebApplicationContext} * created by this context loader. * <p>The default implementation is empty but can be overridden in subclasses * to customize {@code DefaultListableBeanFactory}'s standard settings. * @param beanFactory the bean factory created by this context loader * @param webMergedConfig the merged context configuration to use to load the * web application context * @see #loadContext(MergedContextConfiguration) * @see DefaultListableBeanFactory#setAllowBeanDefinitionOverriding * @see DefaultListableBeanFactory#setAllowEagerClassLoading * @see DefaultListableBeanFactory#setAllowCircularReferences * @see DefaultListableBeanFactory#setAllowRawInjectionDespiteWrapping */ protected void customizeBeanFactory(DefaultListableBeanFactory beanFactory, WebMergedContextConfiguration webMergedConfig) { } /** * Load bean definitions into the supplied {@link GenericWebApplicationContext context} * from the locations or classes in the supplied {@code WebMergedContextConfiguration}. * <p>Concrete subclasses must provide an appropriate implementation. * @param context the context into which the bean definitions should be loaded * @param webMergedConfig the merged context configuration to use to load the * web application context * @see #loadContext(MergedContextConfiguration) */ protected abstract void loadBeanDefinitions(GenericWebApplicationContext context, WebMergedContextConfiguration webMergedConfig); /** * Customize the {@link GenericWebApplicationContext} created by this context * loader <i>after</i> bean definitions have been loaded into the context but * <i>before</i> the context is refreshed. * <p>The default implementation simply delegates to * {@link AbstractContextLoader#customizeContext(ConfigurableApplicationContext, MergedContextConfiguration)}. * @param context the newly created web application context * @param webMergedConfig the merged context configuration to use to load the * web application context * @see #loadContext(MergedContextConfiguration) * @see #customizeContext(ConfigurableApplicationContext, MergedContextConfiguration) */ protected void customizeContext(GenericWebApplicationContext context, WebMergedContextConfiguration webMergedConfig) { super.customizeContext(context, webMergedConfig); } // ContextLoader /** * {@code AbstractGenericWebContextLoader} should be used as a * {@link org.springframework.test.context.SmartContextLoader SmartContextLoader}, * not as a legacy {@link org.springframework.test.context.ContextLoader ContextLoader}. * Consequently, this method is not supported. * @see org.springframework.test.context.ContextLoader#loadContext(java.lang.String[]) * @throws UnsupportedOperationException in this implementation */ @Override public final ApplicationContext loadContext(String... locations) throws Exception { throw new UnsupportedOperationException( "AbstractGenericWebContextLoader does not support the loadContext(String... locations) method"); } }