Java tutorial
/* * Copyright 2002-2017 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 * * https://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.context.support; import org.springframework.beans.BeansException; import org.springframework.context.ApplicationContext; import org.springframework.core.io.ClassPathResource; import org.springframework.core.io.Resource; import org.springframework.lang.Nullable; import org.springframework.util.Assert; /** * Standalone XML application context, taking the context definition files * from the class path, interpreting plain paths as class path resource names * that include the package path (e.g. "mypackage/myresource.txt"). Useful for * test harnesses as well as for application contexts embedded within JARs. * * <p>The config location defaults can be overridden via {@link #getConfigLocations}, * Config locations can either denote concrete files like "/myfiles/context.xml" * or Ant-style patterns like "/myfiles/*-context.xml" (see the * {@link org.springframework.util.AntPathMatcher} javadoc for pattern details). * * <p>Note: In case of multiple config locations, later bean definitions will * override ones defined in earlier loaded files. This can be leveraged to * deliberately override certain bean definitions via an extra XML file. * * <p><b>This is a simple, one-stop shop convenience ApplicationContext. * Consider using the {@link GenericApplicationContext} class in combination * with an {@link org.springframework.beans.factory.xml.XmlBeanDefinitionReader} * for more flexible context setup.</b> * * @author Rod Johnson * @author Juergen Hoeller * @see #getResource * @see #getResourceByPath * @see GenericApplicationContext */ public class ClassPathXmlApplicationContext extends AbstractXmlApplicationContext { @Nullable private Resource[] configResources; /** * Create a new ClassPathXmlApplicationContext for bean-style configuration. * @see #setConfigLocation * @see #setConfigLocations * @see #afterPropertiesSet() */ public ClassPathXmlApplicationContext() { } /** * Create a new ClassPathXmlApplicationContext for bean-style configuration. * @param parent the parent context * @see #setConfigLocation * @see #setConfigLocations * @see #afterPropertiesSet() */ public ClassPathXmlApplicationContext(ApplicationContext parent) { super(parent); } /** * Create a new ClassPathXmlApplicationContext, loading the definitions * from the given XML file and automatically refreshing the context. * @param configLocation resource location * @throws BeansException if context creation failed */ public ClassPathXmlApplicationContext(String configLocation) throws BeansException { this(new String[] { configLocation }, true, null); } /** * Create a new ClassPathXmlApplicationContext, loading the definitions * from the given XML files and automatically refreshing the context. * @param configLocations array of resource locations * @throws BeansException if context creation failed */ public ClassPathXmlApplicationContext(String... configLocations) throws BeansException { this(configLocations, true, null); } /** * Create a new ClassPathXmlApplicationContext with the given parent, * loading the definitions from the given XML files and automatically * refreshing the context. * @param configLocations array of resource locations * @param parent the parent context * @throws BeansException if context creation failed */ public ClassPathXmlApplicationContext(String[] configLocations, @Nullable ApplicationContext parent) throws BeansException { this(configLocations, true, parent); } /** * Create a new ClassPathXmlApplicationContext, loading the definitions * from the given XML files. * @param configLocations array of resource locations * @param refresh whether to automatically refresh the context, * loading all bean definitions and creating all singletons. * Alternatively, call refresh manually after further configuring the context. * @throws BeansException if context creation failed * @see #refresh() */ public ClassPathXmlApplicationContext(String[] configLocations, boolean refresh) throws BeansException { this(configLocations, refresh, null); } /** * Create a new ClassPathXmlApplicationContext with the given parent, * loading the definitions from the given XML files. * @param configLocations array of resource locations * @param refresh whether to automatically refresh the context, * loading all bean definitions and creating all singletons. * Alternatively, call refresh manually after further configuring the context. * @param parent the parent context * @throws BeansException if context creation failed * @see #refresh() */ public ClassPathXmlApplicationContext(String[] configLocations, boolean refresh, @Nullable ApplicationContext parent) throws BeansException { super(parent); setConfigLocations(configLocations); if (refresh) { refresh(); } } /** * Create a new ClassPathXmlApplicationContext, loading the definitions * from the given XML file and automatically refreshing the context. * <p>This is a convenience method to load class path resources relative to a * given Class. For full flexibility, consider using a GenericApplicationContext * with an XmlBeanDefinitionReader and a ClassPathResource argument. * @param path relative (or absolute) path within the class path * @param clazz the class to load resources with (basis for the given paths) * @throws BeansException if context creation failed * @see org.springframework.core.io.ClassPathResource#ClassPathResource(String, Class) * @see org.springframework.context.support.GenericApplicationContext * @see org.springframework.beans.factory.xml.XmlBeanDefinitionReader */ public ClassPathXmlApplicationContext(String path, Class<?> clazz) throws BeansException { this(new String[] { path }, clazz); } /** * Create a new ClassPathXmlApplicationContext, loading the definitions * from the given XML files and automatically refreshing the context. * @param paths array of relative (or absolute) paths within the class path * @param clazz the class to load resources with (basis for the given paths) * @throws BeansException if context creation failed * @see org.springframework.core.io.ClassPathResource#ClassPathResource(String, Class) * @see org.springframework.context.support.GenericApplicationContext * @see org.springframework.beans.factory.xml.XmlBeanDefinitionReader */ public ClassPathXmlApplicationContext(String[] paths, Class<?> clazz) throws BeansException { this(paths, clazz, null); } /** * Create a new ClassPathXmlApplicationContext with the given parent, * loading the definitions from the given XML files and automatically * refreshing the context. * @param paths array of relative (or absolute) paths within the class path * @param clazz the class to load resources with (basis for the given paths) * @param parent the parent context * @throws BeansException if context creation failed * @see org.springframework.core.io.ClassPathResource#ClassPathResource(String, Class) * @see org.springframework.context.support.GenericApplicationContext * @see org.springframework.beans.factory.xml.XmlBeanDefinitionReader */ public ClassPathXmlApplicationContext(String[] paths, Class<?> clazz, @Nullable ApplicationContext parent) throws BeansException { super(parent); Assert.notNull(paths, "Path array must not be null"); Assert.notNull(clazz, "Class argument must not be null"); this.configResources = new Resource[paths.length]; for (int i = 0; i < paths.length; i++) { this.configResources[i] = new ClassPathResource(paths[i], clazz); } refresh(); } @Override @Nullable protected Resource[] getConfigResources() { return this.configResources; } }