Java tutorial
/* * Assurance * * Created by Mark Johnson * * Copyright (c) 2015 Digital Generalists, LLC. * */ /* * Copyright 2015 Digital Generalists, LLC. * * 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.digitalgeneralists.assurance.ui.workers; import java.util.ArrayList; import java.util.List; import java.util.concurrent.ExecutionException; import javax.swing.SwingWorker; import org.apache.log4j.Logger; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.digitalgeneralists.assurance.model.IModelDelegate; import com.digitalgeneralists.assurance.model.entities.ApplicationConfiguration; import com.digitalgeneralists.assurance.model.entities.ScanDefinition; import com.digitalgeneralists.assurance.notification.INotificationProvider; import com.digitalgeneralists.assurance.notification.events.ApplicationConfigurationLoadedEvent; import com.digitalgeneralists.assurance.notification.events.ScanDefinitionsLoadedEvent; public class InitializeApplicationStateWorker extends SwingWorker<List<Object>, Object> { private Logger logger = Logger.getLogger(InitializeApplicationStateWorker.class); private INotificationProvider notifier; public InitializeApplicationStateWorker(INotificationProvider notifier) { this.notifier = notifier; } @Override protected List<Object> doInBackground() throws Exception { List<Object> bootstrapObjects = new ArrayList<Object>(); List<ScanDefinition> scanDefinitions = null; ApplicationConfiguration config = null; // Because we are operating in a Swing application, the session context // closes after the initial bootstrap run. There appears to be an // "application"-level session configuration that should enable the // behavior we want for a desktop application, but there is no documentation // for it that I can find. // So, Assurance mimics a web app request/response // cycle for calls into the model delegate through the Swing // application. All calls to the model initiated directly from the UI // essentially operate as a new "request" and rebuild the Hibernate and // Spring session contexts for use within that operation. ClassPathXmlApplicationContext springContext = null; try { springContext = new ClassPathXmlApplicationContext("/META-INF/spring/app-context.xml"); IModelDelegate modelDelegate = (IModelDelegate) springContext.getBean("ModelDelegate"); scanDefinitions = modelDelegate.getScanDefinitions(); config = modelDelegate.getApplicationConfiguration(); if (scanDefinitions != null) { bootstrapObjects.add(scanDefinitions); } if (config != null) { bootstrapObjects.add(config); } modelDelegate = null; } finally { if (springContext != null) { springContext.close(); } springContext = null; } return bootstrapObjects; } @Override protected void done() { List<Object> loadedObjects = null; try { loadedObjects = this.get(); for (int i = 0; i < loadedObjects.size(); i++) { Object loadedObject = loadedObjects.get(i); // NOTE: The nature of this check isn't ideal. It won't scale once we add multiple lists. if ((loadedObject != null) && (loadedObject instanceof List<?>)) { this.notifier.fireEvent(new ScanDefinitionsLoadedEvent(loadedObject)); } if ((loadedObject != null) && (loadedObject instanceof ApplicationConfiguration)) { this.notifier.fireEvent(new ApplicationConfigurationLoadedEvent(loadedObject)); } } } catch (InterruptedException e) { logger.info("Application bootstrap was aborted."); } catch (ExecutionException e) { logger.error(e); } finally { loadedObjects = null; this.notifier = null; this.logger = null; } } }