/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.shindig.common.servlet;
import com.google.inject.Injector;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.UnavailableException;
import javax.servlet.http.HttpServlet;
/**
* Supports DI for servlets. Can't handle ctor injection since
* the servlet spec requires configuration being done in init().
*/
public abstract class InjectedServlet extends HttpServlet {
protected Injector injector;
@Override public void init(ServletConfig config) throws ServletException {
super.init(config);
ServletContext context = config.getServletContext();
injector = (Injector)
context.getAttribute(GuiceServletContextListener.INJECTOR_ATTRIBUTE);
if (injector == null) {
throw new UnavailableException(
"Guice Injector not found! Make sure you registered " +
GuiceServletContextListener.class.getName() + " as a listener");
}
injector.injectMembers(this);
}
}