Java tutorial
/* * Copyright (c) 2012-2014, Parallel Universe Software Co. All rights reserved. * * This program and the accompanying materials are dual-licensed under * either the terms of the Eclipse Public License v1.0 as published by * the Eclipse Foundation * * or (per the licensee's choosing) * * under the terms of the GNU Lesser General Public License version 3.0 * as published by the Free Software Foundation. */ package co.paralleluniverse.common.spring; import com.google.common.base.Throwables; import java.lang.management.ManagementFactory; import java.lang.reflect.Constructor; import java.lang.reflect.Method; import java.util.Arrays; import java.util.Collection; import java.util.HashMap; import java.util.HashSet; import java.util.Map; import java.util.Properties; import java.util.Set; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.BeansException; import org.springframework.beans.MutablePropertyValues; import org.springframework.beans.PropertyValue; import org.springframework.beans.factory.BeanFactory; import org.springframework.beans.factory.config.BeanDefinition; import org.springframework.beans.factory.config.BeanFactoryPostProcessor; import org.springframework.beans.factory.config.BeanPostProcessor; import org.springframework.beans.factory.config.BeanReference; import org.springframework.beans.factory.config.ConfigurableListableBeanFactory; import org.springframework.beans.factory.config.ConstructorArgumentValues; import org.springframework.beans.factory.config.ConstructorArgumentValues.ValueHolder; import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer; import org.springframework.beans.factory.support.BeanDefinitionRegistry; import org.springframework.beans.factory.support.DefaultListableBeanFactory; import org.springframework.beans.factory.support.GenericBeanDefinition; import org.springframework.beans.factory.support.InstantiationStrategy; import org.springframework.beans.factory.support.RootBeanDefinition; import org.springframework.beans.factory.xml.XmlBeanDefinitionReader; import org.springframework.context.ConfigurableApplicationContext; import org.springframework.context.support.GenericApplicationContext; import org.springframework.core.io.Resource; import org.springframework.jmx.export.MBeanExporter; import org.springframework.jmx.export.annotation.AnnotationJmxAttributeSource; import org.springframework.jmx.export.assembler.MetadataMBeanInfoAssembler; /** * Spring helper functions. * * @author pron */ public final class SpringContainerHelper { private static final Logger LOG = LoggerFactory.getLogger(SpringContainerHelper.class); public static ConfigurableApplicationContext createContext(String defaultDomain, Resource xmlResource, Object properties, BeanFactoryPostProcessor beanFactoryPostProcessor) { LOG.info("JAVA: {} {}, {}", new Object[] { System.getProperty("java.runtime.name"), System.getProperty("java.runtime.version"), System.getProperty("java.vendor") }); LOG.info("OS: {} {}, {}", new Object[] { System.getProperty("os.name"), System.getProperty("os.version"), System.getProperty("os.arch") }); LOG.info("DIR: {}", System.getProperty("user.dir")); final DefaultListableBeanFactory beanFactory = createBeanFactory(); final GenericApplicationContext context = new GenericApplicationContext(beanFactory); context.registerShutdownHook(); final PropertyPlaceholderConfigurer propertyPlaceholderConfigurer = new PropertyPlaceholderConfigurer(); propertyPlaceholderConfigurer .setSystemPropertiesMode(PropertyPlaceholderConfigurer.SYSTEM_PROPERTIES_MODE_OVERRIDE); if (properties != null) { if (properties instanceof Resource) propertyPlaceholderConfigurer.setLocation((Resource) properties); else if (properties instanceof Properties) propertyPlaceholderConfigurer.setProperties((Properties) properties); else throw new IllegalArgumentException( "Properties argument - " + properties + " - is of an unhandled type"); } context.addBeanFactoryPostProcessor(propertyPlaceholderConfigurer); // MBean exporter //final MBeanExporter mbeanExporter = new AnnotationMBeanExporter(); //mbeanExporter.setServer(ManagementFactory.getPlatformMBeanServer()); //beanFactory.registerSingleton("mbeanExporter", mbeanExporter); context.registerBeanDefinition("mbeanExporter", getMBeanExporterBeanDefinition(defaultDomain)); // inject bean names into components context.addBeanFactoryPostProcessor(new BeanFactoryPostProcessor() { @Override public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException { for (String beanName : beanFactory.getBeanDefinitionNames()) { try { final BeanDefinition beanDefinition = beanFactory.getBeanDefinition(beanName); if (beanDefinition.getBeanClassName() != null) { // van be null for factory methods final Class<?> beanClass = Class.forName(beanDefinition.getBeanClassName()); if (Component.class.isAssignableFrom(beanClass)) beanDefinition.getConstructorArgumentValues().addIndexedArgumentValue(0, beanName); } } catch (Exception ex) { LOG.error("Error loading bean " + beanName + " definition.", ex); throw new Error(ex); } } } }); if (beanFactoryPostProcessor != null) context.addBeanFactoryPostProcessor(beanFactoryPostProcessor); beanFactory.registerCustomEditor(org.w3c.dom.Element.class, co.paralleluniverse.common.util.DOMElementProprtyEditor.class); final Map<String, Object> beans = new HashMap<String, Object>(); beanFactory.addBeanPostProcessor(new BeanPostProcessor() { @Override public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException { LOG.info("Loading bean {} [{}]", beanName, bean.getClass().getName()); beans.put(beanName, bean); if (bean instanceof Service) { final BeanDefinition beanDefinition = beanFactory.getBeanDefinition(beanName); Collection<String> dependencies = getBeanDependencies(beanDefinition); for (String dependeeName : dependencies) { Object dependee = beanFactory.getBean(dependeeName); if (dependee instanceof Service) { ((Service) dependee).addDependedBy((Service) bean); ((Service) bean).addDependsOn((Service) dependee); } } } return bean; } @Override public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException { LOG.info("Bean {} [{}] loaded", beanName, bean.getClass().getName()); return bean; } }); final XmlBeanDefinitionReader xmlReader = new XmlBeanDefinitionReader((BeanDefinitionRegistry) beanFactory); xmlReader.loadBeanDefinitions(xmlResource); // start container context.refresh(); // Call .postInit() on all Components // There's probably a better way to do this try { for (Map.Entry<String, Object> entry : beans.entrySet()) { final String beanName = entry.getKey(); final Object bean = entry.getValue(); if (bean instanceof Component) { LOG.info("Performing post-initialization on bean {} [{}]", beanName, bean.getClass().getName()); ((Component) bean).postInit(); } } } catch (Exception e) { throw Throwables.propagate(e); } return context; } public static Collection<String> getBeanDependencies(BeanDefinition beanDefinition) { Set<String> dependencies = new HashSet<String>(); if (beanDefinition.getDependsOn() != null) dependencies.addAll(Arrays.asList(beanDefinition.getDependsOn())); for (ValueHolder value : beanDefinition.getConstructorArgumentValues().getGenericArgumentValues()) { if (value.getValue() instanceof BeanReference) dependencies.add(((BeanReference) value.getValue()).getBeanName()); } for (ValueHolder value : beanDefinition.getConstructorArgumentValues().getIndexedArgumentValues() .values()) { if (value.getValue() instanceof BeanReference) dependencies.add(((BeanReference) value.getValue()).getBeanName()); } for (PropertyValue value : beanDefinition.getPropertyValues().getPropertyValueList()) { if (value.getValue() instanceof BeanReference) dependencies.add(((BeanReference) value.getValue()).getBeanName()); } return dependencies; } /** * adds hooks to capture autowired constructor args and add them as dependencies * * @return */ private static DefaultListableBeanFactory createBeanFactory() { return new DefaultListableBeanFactory() { { final InstantiationStrategy is = getInstantiationStrategy(); setInstantiationStrategy(new InstantiationStrategy() { @Override public Object instantiate(RootBeanDefinition beanDefinition, String beanName, BeanFactory owner) throws BeansException { return is.instantiate(beanDefinition, beanName, owner); } @Override public Object instantiate(RootBeanDefinition beanDefinition, String beanName, BeanFactory owner, Constructor<?> ctor, Object[] args) throws BeansException { final Object bean = is.instantiate(beanDefinition, beanName, owner, ctor, args); addDependencies(bean, args); return bean; } @Override public Object instantiate(RootBeanDefinition beanDefinition, String beanName, BeanFactory owner, Object factoryBean, Method factoryMethod, Object[] args) throws BeansException { final Object bean = is.instantiate(beanDefinition, beanName, owner, factoryBean, factoryMethod, args); addDependencies(bean, args); return bean; } }); } private void addDependencies(Object bean, Object[] args) { if (bean instanceof Service) { for (Object arg : args) { if (arg instanceof Service) { ((Service) arg).addDependedBy((Service) bean); ((Service) bean).addDependsOn((Service) arg); } } } } }; } public static BeanDefinition defineBean(Class<?> clazz, ConstructorArgumentValues constructorArgs, MutablePropertyValues properties) { GenericBeanDefinition bean = new GenericBeanDefinition(); bean.setBeanClass(clazz); bean.setAutowireCandidate(true); bean.setConstructorArgumentValues(constructorArgs); bean.setPropertyValues(properties); return bean; } private static BeanDefinition getMBeanExporterBeanDefinition(String defaultDomain) { final AnnotationJmxAttributeSource annotationSource = new AnnotationJmxAttributeSource(); final GenericBeanDefinition bean = new GenericBeanDefinition(); bean.setBeanClass(MBeanExporter.class); MutablePropertyValues properties = new MutablePropertyValues(); properties.add("server", ManagementFactory.getPlatformMBeanServer()); properties.add("autodetectMode", MBeanExporter.AUTODETECT_ASSEMBLER); properties.add("assembler", new MetadataMBeanInfoAssembler(annotationSource)); properties.add("namingStrategy", new MBeanNamingStrategy(annotationSource).setDefaultDomain(defaultDomain)); bean.setPropertyValues(properties); return bean; } public static ConstructorArgumentValues constructorArgs(Object... args) { ConstructorArgumentValues cav = new ConstructorArgumentValues(); for (int i = 0; i < args.length; i++) cav.addIndexedArgumentValue(i, args[i]); return cav; } public static MutablePropertyValues properties(Map<String, ? extends Object> properties) { MutablePropertyValues mpv = new MutablePropertyValues(properties); return mpv; } private SpringContainerHelper() { } }