| /* |
| * Copyright 2013 gitblit.com. |
| * |
| * 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 com.gitblit.dagger; |
| |
| import javax.servlet.ServletContext; |
| import javax.servlet.ServletContextEvent; |
| import javax.servlet.ServletContextListener; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import dagger.ObjectGraph; |
| |
| /** |
| * Dagger servlet context listener is a context listener that uses Dagger to |
| * instantiate and inject servlets, filters, and anything else you might want. |
| * |
| * @author James Moger |
| * |
| */ |
| public abstract class DaggerContext implements ServletContextListener { |
| |
| public static final String INJECTOR_NAME = ObjectGraph.class.getName(); |
| |
| protected final Logger logger = LoggerFactory.getLogger(getClass()); |
| |
| protected abstract Object [] getModules(); |
| |
| protected abstract void destroyContext(ServletContext context); |
| |
| protected ObjectGraph getInjector(ServletContext context) { |
| Object o = context.getAttribute(INJECTOR_NAME); |
| if (o == null) { |
| logger.debug("instantiating Dagger modules"); |
| Object [] modules = getModules(); |
| logger.debug("getting Dagger injector"); |
| try { |
| o = ObjectGraph.create(modules); |
| logger.debug("setting Dagger injector into {} attribute", INJECTOR_NAME); |
| context.setAttribute(INJECTOR_NAME, o); |
| } catch (Throwable t) { |
| logger.error("an error occurred creating the Dagger injector", t); |
| } |
| } |
| return (ObjectGraph) o; |
| } |
| |
| @Override |
| public final void contextDestroyed(ServletContextEvent contextEvent) { |
| ServletContext context = contextEvent.getServletContext(); |
| context.removeAttribute(INJECTOR_NAME); |
| destroyContext(context); |
| } |
| } |