Java tutorial
/* * Copyright 2013 the original author or authors. * * 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 org.springframework.xd.dirt.container; import java.io.File; import java.lang.management.ManagementFactory; import java.net.InetAddress; import java.net.UnknownHostException; import java.util.UUID; import org.apache.commons.lang.StringUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.log4j.Appender; import org.apache.log4j.Logger; import org.apache.log4j.RollingFileAppender; import org.springframework.context.ApplicationContext; import org.springframework.context.ApplicationListener; import org.springframework.context.ConfigurableApplicationContext; import org.springframework.context.SmartLifecycle; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.util.Assert; import org.springframework.xd.dirt.server.options.XDPropertyKeys; /** * @author Mark Fisher * @author Jennifer Hickey * @author David Turanski * @author Ilayaperumal Gopinathan */ public class XDContainer implements SmartLifecycle { private static final String LINE_SEPARATOR = System.getProperty("line.separator"); private static final Log logger = LogFactory.getLog(XDContainer.class); private volatile ApplicationContext launcherContext; /** * Base location for XD config files. Chosen so as not to collide with user provided content. */ public static final String XD_CONFIG_ROOT = "META-INF/spring-xd/"; /** * Where container related config files reside. */ public static final String XD_INTERNAL_CONFIG_ROOT = XD_CONFIG_ROOT + "internal/"; private static final String CORE_CONFIG = XD_INTERNAL_CONFIG_ROOT + "container.xml"; // TODO: consider moving to a file: location pattern within $XD_HOME private static final String PLUGIN_CONFIGS = "classpath*:" + XD_CONFIG_ROOT + "plugins/*.xml"; private static final String LOG4J_FILE_APPENDER = "file"; private volatile ConfigurableApplicationContext context; private final String id; private String hostName; private String ipAddress; private volatile String jvmName; private volatile boolean containerRunning; /** * Creates a container with a given id * * @param id the id */ public XDContainer(String id) { this.id = id; } /** * Default constructor generates a random id */ public XDContainer() { this.id = UUID.randomUUID().toString(); } public String getId() { return (this.context != null) ? this.context.getId() : ""; } public String getHostName() { try { this.hostName = InetAddress.getLocalHost().getHostName(); } catch (UnknownHostException uhe) { this.hostName = "unknown"; } return this.hostName; } public String getIpAddress() { try { this.ipAddress = InetAddress.getLocalHost().getHostAddress(); } catch (UnknownHostException uhe) { this.ipAddress = "unknown"; } return this.ipAddress; } public String getJvmName() { synchronized (this) { if (this.jvmName == null) { this.jvmName = ManagementFactory.getRuntimeMXBean().getName(); } } return this.jvmName; } @Override public int getPhase() { return 0; } @Override public boolean isAutoStartup() { return true; } @Override public boolean isRunning() { return this.context != null; } private boolean isContainerRunning() { return containerRunning; } public void setLauncherContext(ApplicationContext context) { this.launcherContext = context; } public void setContext(ConfigurableApplicationContext context) { this.context = context; } public ApplicationContext getApplicationContext() { return this.context; } @Override public void start() { this.context = new ClassPathXmlApplicationContext(new String[] { CORE_CONFIG, PLUGIN_CONFIGS }, false); context.setId(this.id); updateLoggerFilename(); Assert.notNull(launcherContext, "no Container launcher ApplicationContext has been set"); ApplicationContext globalContext = launcherContext.getParent(); Assert.notNull(globalContext, "no global context has been set"); context.setParent(globalContext); context.registerShutdownHook(); context.refresh(); this.containerRunning = true; context.publishEvent(new ContainerStartedEvent(this)); if (logger.isInfoEnabled()) { logger.info("started container: " + context.getId()); } } @Override public void stop() { if (this.context != null && isContainerRunning()) { this.containerRunning = false; // Publish the container stopped event before the context is closed. this.context.publishEvent(new ContainerStoppedEvent(this)); this.context.close(); ((ConfigurableApplicationContext) context.getParent()).close(); if (logger.isInfoEnabled()) { final String message = "Stopped container: " + this.jvmName; final StringBuilder sb = new StringBuilder(LINE_SEPARATOR); sb.append(StringUtils.rightPad("", message.length(), "-")).append(LINE_SEPARATOR).append(message) .append(LINE_SEPARATOR).append(StringUtils.rightPad("", message.length(), "-")) .append(LINE_SEPARATOR); logger.info(sb.toString()); } } } @Override public void stop(Runnable callback) { this.stop(); callback.run(); } public void addListener(ApplicationListener<?> listener) { Assert.state(this.context != null, "context is not initialized"); this.context.addApplicationListener(listener); } /** * Update container log appender file name with container id */ private void updateLoggerFilename() { Appender appender = Logger.getRootLogger().getAppender(LOG4J_FILE_APPENDER); if (appender instanceof RollingFileAppender) { String xdHome = context.getEnvironment().getProperty(XDPropertyKeys.XD_HOME); ((RollingFileAppender) appender) .setFile(new File(xdHome).getAbsolutePath() + "/logs/container-" + this.getId() + ".log"); ((RollingFileAppender) appender).activateOptions(); } } public int getJmxPort() { return Integer.valueOf(this.context.getEnvironment().getProperty(XDPropertyKeys.XD_JMX_PORT)); } public boolean isJmxEnabled() { return Boolean.valueOf(this.context.getEnvironment().getProperty(XDPropertyKeys.XD_JMX_ENABLED)); } public String getPropertyValue(String key) { return this.context.getEnvironment().getProperty(key); } }