/*
* Copyright 2007-2010 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.impalaframework.web.spring.integration;
import java.util.Map;
import javax.servlet.Servlet;
import org.springframework.context.ApplicationContext;
import org.springframework.util.Assert;
import org.springframework.web.servlet.FrameworkServlet;
/**
* Extension of {@link ServletFactoryBean} which is designed specifically to
* handle non-Impala subclasses of Spring MVC's framework servlet. In addition
* to instantiating the servlet concerned (done in
* {@link ServletFactoryBean#afterPropertiesSet()}) this implementation will
* also instantiate {@link InternalFrameworkIntegrationServlet}, and set the
* Spring MVC's {@link FrameworkServlet} instance as a delegate. It will also
* publish the current {@link ApplicationContext} using the
* {@link FrameworkServlet#getServletContextAttributeName()}, so that the
* {@link FrameworkServlet} instance can find the application context to use,
* rather than instantiate its own.
*
* @author Phil Zoio
*/
public class FrameworkIntegrationServletFactoryBean extends ServletFactoryBean {
private String contextAttribute;
private InternalFrameworkIntegrationServlet integrationServlet;
@Override
public void setServletClass(Class<?> servletClass) {
Assert.isTrue(FrameworkServlet.class.isAssignableFrom(servletClass), "Servlet class must be assignable to FrameworkServlet");
super.setServletClass(servletClass);
}
@Override
public void afterPropertiesSet() throws Exception {
//this will set up the delegate servlet
super.afterPropertiesSet();
completeAfterProperties();
}
void completeAfterProperties() throws Exception {
//get the FrameworkServlet instance
FrameworkServlet delegate = (FrameworkServlet) super.getObject();
//set up the integration servlet
integrationServlet = new InternalFrameworkIntegrationServlet();
integrationServlet.setApplicationContext(getApplicationContext());
integrationServlet.setSetContextClassLoader(true);
integrationServlet.setDelegateServlet(delegate);
}
@Override
protected void initServletProperties(Servlet servlet) {
//check the context attribute
final Map<String, String> initParameters = super.getInitParameters();
final String attribute = initParameters.get("contextAttribute");
if (attribute == null) {
this.contextAttribute = "someattribute";
initParameters.put("contextAttribute", this.contextAttribute);
} else {
this.contextAttribute = attribute;
}
//bind dispatcher servlet to context attribute
getServletContext().setAttribute(contextAttribute, getApplicationContext());
}
@Override
public Class<?> getObjectType() {
return InternalFrameworkIntegrationServlet.class;
}
@Override
public InternalFrameworkIntegrationServlet getObject() throws Exception {
return integrationServlet;
}
@Override
public void destroy() throws Exception {
super.destroy();
integrationServlet.destroy();
getServletContext().removeAttribute(contextAttribute);
//FIXME only do this if published context
String attrName = FrameworkServlet.SERVLET_CONTEXT_PREFIX + getServletName();
getServletContext().removeAttribute(attrName);
}
}