org.springframework.web.context.support.SpringBeanAutowiringSupport Maven / Gradle / Ivy
/*
* Copyright 2002-2012 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.web.context.support;
import javax.servlet.ServletContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.web.context.ContextLoader;
import org.springframework.web.context.WebApplicationContext;
/**
* Convenient base class for self-autowiring classes that gets constructed
* within a Spring-based web application. Resolves {@code @Autowired}
* annotations in the endpoint class against beans in the current Spring
* root web application context (as determined by the current thread's
* context ClassLoader, which needs to be the web application's ClassLoader).
* Can alternatively be used as a delegate instead of as a base class.
*
* A typical usage of this base class is a JAX-WS endpoint class:
* Such a Spring-based JAX-WS endpoint implementation will follow the
* standard JAX-WS contract for endpoint classes but will be 'thin'
* in that it delegates the actual work to one or more Spring-managed
* service beans - typically obtained using {@code @Autowired}.
* The lifecycle of such an endpoint instance will be managed by the
* JAX-WS runtime, hence the need for this base class to provide
* {@code @Autowired} processing based on the current Spring context.
*
*
NOTE: If there is an explicit way to access the ServletContext,
* prefer such a way over using this class. The {@link WebApplicationContextUtils}
* class allows for easy access to the Spring root web application context
* based on the ServletContext.
*
* @author Juergen Hoeller
* @since 2.5.1
* @see WebApplicationObjectSupport
*/
public abstract class SpringBeanAutowiringSupport {
private static final Log logger = LogFactory.getLog(SpringBeanAutowiringSupport.class);
/**
* This constructor performs injection on this instance,
* based on the current web application context.
*
Intended for use as a base class.
* @see #processInjectionBasedOnCurrentContext
*/
public SpringBeanAutowiringSupport() {
processInjectionBasedOnCurrentContext(this);
}
/**
* Process {@code @Autowired} injection for the given target object,
* based on the current web application context.
*
Intended for use as a delegate.
* @param target the target object to process
* @see org.springframework.web.context.ContextLoader#getCurrentWebApplicationContext()
*/
public static void processInjectionBasedOnCurrentContext(Object target) {
Assert.notNull(target, "Target object must not be null");
WebApplicationContext cc = ContextLoader.getCurrentWebApplicationContext();
if (cc != null) {
AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
bpp.setBeanFactory(cc.getAutowireCapableBeanFactory());
bpp.processInjection(target);
}
else {
if (logger.isDebugEnabled()) {
logger.debug("Current WebApplicationContext is not available for processing of " +
ClassUtils.getShortName(target.getClass()) + ": " +
"Make sure this class gets constructed in a Spring web application. Proceeding without injection.");
}
}
}
/**
* Process {@code @Autowired} injection for the given target object,
* based on the current root web application context as stored in the ServletContext.
*
Intended for use as a delegate.
* @param target the target object to process
* @param servletContext the ServletContext to find the Spring web application context in
* @see WebApplicationContextUtils#getWebApplicationContext(javax.servlet.ServletContext)
*/
public static void processInjectionBasedOnServletContext(Object target, ServletContext servletContext) {
Assert.notNull(target, "Target object must not be null");
WebApplicationContext cc = WebApplicationContextUtils.getRequiredWebApplicationContext(servletContext);
AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
bpp.setBeanFactory(cc.getAutowireCapableBeanFactory());
bpp.processInjection(target);
}
}