Java tutorial
/** * The contents of this file are subject to the license and copyright * detailed in the LICENSE and NOTICE files at the root of the source * tree and available online at * * http://www.dspace.org/license/ */ package org.dspace.servicemanager.spring; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; import org.dspace.kernel.config.SpringLoader; import org.dspace.servicemanager.DSpaceServiceManager; import org.dspace.servicemanager.ServiceManagerSystem; import org.dspace.servicemanager.config.DSpaceConfigurationService; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.BeansException; import org.springframework.beans.factory.ListableBeanFactory; import org.springframework.beans.factory.NoSuchBeanDefinitionException; import org.springframework.beans.factory.config.AutowireCapableBeanFactory; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; /** * This is the Spring implementation of the service manager. * * @author Aaron Zeckoski (azeckoski @ gmail.com) */ public final class SpringServiceManager implements ServiceManagerSystem { private static Logger log = LoggerFactory.getLogger(SpringServiceManager.class); private ClassPathXmlApplicationContext applicationContext; /** * @return the parent core Spring {@link ApplicationContext} */ public ClassPathXmlApplicationContext getApplicationContext() { return applicationContext; } /** * @return the current spring bean factory OR null if there is not one */ public ListableBeanFactory getBeanFactory() { if (applicationContext != null) { return applicationContext.getBeanFactory(); } return null; } private final ServiceManagerSystem parent; private final DSpaceConfigurationService configurationService; private boolean testMode = false; private boolean developmentMode = false; private String[] configPaths = null; /** * For TESTING: * Allows adding extra spring config paths. * * @param testMode if true then do not load the core beans * @param configPaths additional spring config paths within this classloader */ public SpringServiceManager(ServiceManagerSystem parent, DSpaceConfigurationService configurationService, boolean testMode, boolean developmentMode, String... configPaths) { if (parent == null) { throw new IllegalArgumentException("parent SMS cannot be null"); } this.parent = parent; if (configurationService == null) { throw new IllegalArgumentException("configuration service cannot be null"); } this.configurationService = configurationService; this.testMode = testMode; this.developmentMode = developmentMode; this.configPaths = configPaths; } public static final String configPath = "spring/spring-dspace-applicationContext.xml"; public static final String coreResourcePath = "classpath*:spring/spring-dspace-core-services.xml"; public static final String addonResourcePath = "classpath*:spring/spring-dspace-addon-*-services.xml"; @SuppressWarnings("unchecked") public <T> T getServiceByName(String name, Class<T> type) { T bean = null; // handle special case to return the core AC if (ApplicationContext.class.getName().equals(name) && ApplicationContext.class.isAssignableFrom(type)) { bean = (T) getApplicationContext(); } else { if (name != null) { // get by name and type try { bean = (T) applicationContext.getBean(name, type); } catch (BeansException e) { // no luck, try the fall back option bean = null; } } else { // try making up the name based on the type try { bean = (T) applicationContext.getBean(type.getName(), type); } catch (BeansException e) { // no luck, try the fall back option bean = null; } } // if still no luck then try by type only if (name == null && bean == null) { try { Map<String, T> map = applicationContext.getBeansOfType(type); if (map.size() == 1) { // only return the bean if there is exactly one bean = (T) map.values().iterator().next(); } } catch (BeansException e) { // I guess there are no beans of this type bean = null; } } } return bean; } @SuppressWarnings("unchecked") public <T> List<T> getServicesByType(Class<T> type) { ArrayList<T> l = new ArrayList<T>(); Map<String, T> beans; try { beans = applicationContext.getBeansOfType(type, true, true); l.addAll((Collection<? extends T>) beans.values()); } catch (BeansException e) { throw new RuntimeException("Failed to get beans of type (" + type + "): " + e.getMessage(), e); } return l; } public void shutdown() { if (applicationContext != null) { try { applicationContext.close(); } catch (Exception e) { // keep going anyway e.printStackTrace(); } try { applicationContext.destroy(); } catch (Exception e) { // keep going anyway e.printStackTrace(); } applicationContext = null; log.info("Spring Service Manager Shutdown..."); } } public void startup() { long startTime = System.currentTimeMillis(); // get all spring config paths ArrayList<String> pathList = new ArrayList<String>(); pathList.add(configPath); pathList.add(addonResourcePath); if (testMode) { log.warn("TEST Spring Service Manager running in test mode, no core beans will be started"); } else { // only load the core beans when not testing the service manager pathList.add(coreResourcePath); } if (configPaths != null) { pathList.addAll(Arrays.asList(configPaths)); } if (testMode) { log.warn( "TEST Spring Service Manager running in test mode, no dspace home spring files will be loaded"); } else { //Retrieve all our spring file locations depending on the deployed module String[] springLoaderClassNames = configurationService.getPropertyAsType("spring.springloader.modules", new String[0]); if (springLoaderClassNames != null) { for (String springLoaderClassName : springLoaderClassNames) { try { Class<SpringLoader> springLoaderClass = (Class<SpringLoader>) Class .forName(springLoaderClassName.trim()); String[] resourcePaths = springLoaderClass.getConstructor().newInstance() .getResourcePaths(configurationService); if (resourcePaths != null) { pathList.addAll(Arrays.asList(resourcePaths)); } } catch (ClassNotFoundException e) { //Ignore this exception, if we get one this just means that this module isn't loaded } catch (Exception e) { log.error( "Error while retrieving spring resource paths for module: " + springLoaderClassName, e); } } } } String[] allPaths = pathList.toArray(new String[pathList.size()]); applicationContext = new ClassPathXmlApplicationContext(allPaths, false); // Make sure that the spring files from the config directoy can override the spring files from our jars applicationContext.setAllowBeanDefinitionOverriding(true); applicationContext.setAllowCircularReferences(false); //applicationContext.registerShutdownHook(); // this interferes with the kernel shutdown hook // add the config interceptors (partially done in the xml) applicationContext.addBeanFactoryPostProcessor( new DSpaceBeanFactoryPostProcessor(parent, configurationService, testMode)); applicationContext.refresh(); if (developmentMode) { log.warn( "Spring Service Manager is running in developmentMode, services will be loaded on demand only"); // TODO find a way to set this sucker to super duper lazy mode? it is currently not actually doing it } else { applicationContext.getBeanFactory().preInstantiateSingletons(); applicationContext.getBeanFactory().freezeConfiguration(); } long totalTime = System.currentTimeMillis() - startTime; log.info("Spring Service Manager started up in " + totalTime + " ms with " + applicationContext.getBeanDefinitionCount() + " services..."); } @SuppressWarnings("unchecked") public <T> T registerServiceClass(String name, Class<T> type) { if (name == null || type == null) { throw new IllegalArgumentException("name and type must not be null for service registration"); } T service; try { service = (T) applicationContext.getBeanFactory().autowire(type, AutowireCapableBeanFactory.AUTOWIRE_BY_TYPE, true); registerBean(name, service); } catch (BeansException e) { throw new IllegalArgumentException( "Invalid service class (" + type + ") with name (" + name + ") registration: " + e.getMessage(), e); } return service; } public void registerService(String name, Object service) { if (name == null || service == null) { throw new IllegalArgumentException("name and service must not be null for service registration"); } try { applicationContext.getBeanFactory().autowireBean(service); } catch (BeansException e) { throw new IllegalArgumentException( "Invalid service (" + service + ") with name (" + name + ") registration: " + e.getMessage(), e); } registerBean(name, service); } /** * This handles the common part of the 2 types of service * registrations. * * @param name * @param service */ private void registerBean(String name, Object service) { try { applicationContext.getBeanFactory().initializeBean(service, name); applicationContext.getBeanFactory().registerSingleton(name, service); } catch (BeansException e) { throw new IllegalArgumentException( "Invalid service (" + service + ") with name (" + name + ") registration: " + e.getMessage(), e); } } public void unregisterService(String name) { if (applicationContext.containsBean(name)) { try { Object beanInstance = applicationContext.getBean(name); try { applicationContext.getBeanFactory().destroyBean(name, beanInstance); } catch (NoSuchBeanDefinitionException e) { // this happens if the bean was registered manually (annoyingly) DSpaceServiceManager.shutdownService(beanInstance); } } catch (BeansException e) { // nothing to do here, could not find the bean } } } public List<String> getServicesNames() { ArrayList<String> beanNames = new ArrayList<String>(); String[] singletons = applicationContext.getBeanFactory().getSingletonNames(); for (String singleton : singletons) { if (singleton.startsWith("org.springframework.context")) { continue; // skip the spring standard ones } beanNames.add(singleton); } Collections.sort(beanNames); return beanNames; } public boolean isServiceExists(String name) { return applicationContext.containsBean(name); } public Map<String, Object> getServices() { Map<String, Object> services = new HashMap<String, Object>(); String[] singletons = applicationContext.getBeanFactory().getSingletonNames(); for (String singleton : singletons) { if (singleton.startsWith("org.springframework.context")) { continue; // skip the spring standard ones } String beanName = singleton; Object service = applicationContext.getBeanFactory().getSingleton(beanName); if (service == null) { continue; } services.put(beanName, service); } return services; } public void pushConfig(Map<String, String> settings) { throw new UnsupportedOperationException("Not implemented for individual service manager systems"); } }