/*
* Copyright 2002-2016 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.servlet.support;
import org.springframework.util.ObjectUtils;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
/**
* Base class for {@link org.springframework.web.WebApplicationInitializer}
* implementations that register a
* {@link org.springframework.web.servlet.DispatcherServlet DispatcherServlet}
* configured with annotated classes, e.g. Spring's
* {@link org.springframework.context.annotation.Configuration @Configuration} classes.
*
* <p>Concrete implementations are required to implement {@link #getRootConfigClasses()}
* and {@link #getServletConfigClasses()} as well as {@link #getServletMappings()}.
* Further template and customization methods are provided by
* {@link AbstractDispatcherServletInitializer}.
*
* <p>This is the preferred approach for applications that use Java-based
* Spring configuration.
*
* @author Arjen Poutsma
* @author Chris Beams
* @since 3.2
*/
public abstract class AbstractAnnotationConfigDispatcherServletInitializer
extends AbstractDispatcherServletInitializer {
/**
* {@inheritDoc}
* <p>This implementation creates an {@link AnnotationConfigWebApplicationContext},
* providing it the annotated classes returned by {@link #getRootConfigClasses()}.
* Returns {@code null} if {@link #getRootConfigClasses()} returns {@code null}.
*/
@Override
protected WebApplicationContext createRootApplicationContext() {
Class<?>[] configClasses = getRootConfigClasses();
if (!ObjectUtils.isEmpty(configClasses)) {
AnnotationConfigWebApplicationContext rootAppContext = new AnnotationConfigWebApplicationContext();
rootAppContext.register(configClasses);
return rootAppContext;
}
else {
return null;
}
}
/**
* {@inheritDoc}
* <p>This implementation creates an {@link AnnotationConfigWebApplicationContext},
* providing it the annotated classes returned by {@link #getServletConfigClasses()}.
*/
@Override
protected WebApplicationContext createServletApplicationContext() {
AnnotationConfigWebApplicationContext servletAppContext = new AnnotationConfigWebApplicationContext();
Class<?>[] configClasses = getServletConfigClasses();
if (!ObjectUtils.isEmpty(configClasses)) {
servletAppContext.register(configClasses);
}
return servletAppContext;
}
/**
* Specify {@link org.springframework.context.annotation.Configuration @Configuration}
* and/or {@link org.springframework.stereotype.Component @Component} classes to be
* provided to the {@linkplain #createRootApplicationContext() root application context}.
* @return the configuration classes for the root application context, or {@code null}
* if creation and registration of a root context is not desired
*/
protected abstract Class<?>[] getRootConfigClasses();
/**
* Specify {@link org.springframework.context.annotation.Configuration @Configuration}
* and/or {@link org.springframework.stereotype.Component @Component} classes to be
* provided to the {@linkplain #createServletApplicationContext() dispatcher servlet
* application context}.
* @return the configuration classes for the dispatcher servlet application context or
* {@code null} if all configuration is specified through root config classes.
*/
protected abstract Class<?>[] getServletConfigClasses();
}