public void fireLifecycleEvent(String type, Object data) {LifecycleEvent event = new LifecycleEvent(lifecycle, type, data); LifecycleListener interested[] = null;synchronized (listeners) {interested = (LifecycleListener[]) listeners.clone(); // step1}for (int i = 0; i < interested.length; i++)interested[i].lifecycleEvent(event); // step2}

 // implementation of the Lifecycle interface's methodspublic void addLifecycleListener(LifecycleListener listener) {lifecycle.addLifecycleListener(listener);}

public synchronized void start() throws LifecycleException { // SimpleContext.start()if (started)throw new LifecycleException("SimpleContext has already started");// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(BEFORE_START_EVENT, null);started = true;try {// 启动它的组件和子容器，当前程序中，共有两个组件实现了Lifecycle接口，分别是// SimpleLoader类和 SimplePipeline类.// Start our subordinate components, if anyif ((loader != null) && (loader instanceof Lifecycle))((Lifecycle) loader).start(); // highlight line.// Start our child containers, if anyContainer children[] = findChildren();for (int i = 0; i < children.length; i++) {if (children[i] instanceof Lifecycle)((Lifecycle) children[i]).start(); // highlight line.}// Start the Valves in our pipeline (including the basic),// if anyif (pipeline instanceof Lifecycle)((Lifecycle) pipeline).start(); // highlight line.// Notify our interested LifecycleListeners// 组件和子容器都启动完毕后，会触发两个事件：START_EVENT AND AFTER_START_EVENT.lifecycle.fireLifecycleEvent(START_EVENT, null);}catch (Exception e) {e.printStackTrace();}// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(AFTER_START_EVENT, null);}// stop方法 类似于上述的 start方法.public void stop() throws LifecycleException { // SimpleContext.stop() 方法if (!started)throw new LifecycleException("SimpleContext has not been started");// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(BEFORE_STOP_EVENT, null);lifecycle.fireLifecycleEvent(STOP_EVENT, null);started = false;try {// Stop the Valves in our pipeline (including the basic), if anyif (pipeline instanceof Lifecycle) {((Lifecycle) pipeline).stop();}// Stop our child containers, if anyContainer children[] = findChildren();for (int i = 0; i < children.length; i++) {if (children[i] instanceof Lifecycle)((Lifecycle) children[i]).stop();}if ((loader != null) && (loader instanceof Lifecycle)) {((Lifecycle) loader).stop();}}catch (Exception e) {e.printStackTrace();}// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(AFTER_STOP_EVENT, null);}

public synchronized void start() throws LifecycleException {  // SimpleWrapper.start()System.out.println("Starting Wrapper " + name);if (started)throw new LifecycleException("Wrapper already started");// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(BEFORE_START_EVENT, null);started = true;// Start our subordinate components, if anyif ((loader != null) && (loader instanceof Lifecycle))((Lifecycle) loader).start();// Start the Valves in our pipeline (including the basic), if anyif (pipeline instanceof Lifecycle)((Lifecycle) pipeline).start();// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(START_EVENT, null);// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(AFTER_START_EVENT, null);}  

  public void stop() throws LifecycleException { // SimpleWrapper.stop() 方法System.out.println("Stopping wrapper " + name);// Shut down our servlet instance (if it has been initialized)try {instance.destroy();}catch (Throwable t) {}instance = null;if (!started)throw new LifecycleException("Wrapper " + name + " not started");// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(BEFORE_STOP_EVENT, null);// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(STOP_EVENT, null);started = false;// Stop the Valves in our pipeline (including the basic), if anyif (pipeline instanceof Lifecycle) {((Lifecycle) pipeline).stop();}// Stop our subordinate components, if anyif ((loader != null) && (loader instanceof Lifecycle)) {((Lifecycle) loader).stop();}// Notify our interested LifecycleListenerslifecycle.fireLifecycleEvent(AFTER_STOP_EVENT, null);}

public final class Bootstrap {public static void main(String[] args) {// 连接器,创建服务器套接字，维护HttpProcessor 对象池（stack）Connector connector = new HttpConnector(); // servlet最低级容器 Wrapper，用于封装servlet，并提供类加载器，加载相应的servletWrapper wrapper1 = new SimpleWrapper();wrapper1.setName("Primitive");wrapper1.setServletClass("servlet.PrimitiveServlet");Wrapper wrapper2 = new SimpleWrapper();wrapper2.setName("Modern");wrapper2.setServletClass("servlet.ModernServlet");// 将Wrapper容器添加到其父容器ContextContext context = new SimpleContext(); context.addChild(wrapper1);context.addChild(wrapper2);// 映射器Mapper，其作用是通过 请求路径，如 http://localhost:8080/Modern;// 通过HttpProcessor.process() 方法解析reqeust，获取 访问绝对路径 /Modern// 通过在映射器（的map方法）查找该路径对应的容器资源名称(Modern)// 然后还是在其map方法中继续通过容器名称(Modern)映射到servlet名称（servlet.ModernServlet）// 这样才通过 /Modern 映射到对应的servlet访问路径(加载路径，以便类加载器加载)Mapper mapper = new SimpleContextMapper();mapper.setProtocol("http");// 添加生命周期监听器LifecycleListener listener = new SimpleContextLifecycleListener();((Lifecycle) context).addLifecycleListener(listener);context.addMapper(mapper);// 添加类加载器Loader loader = new SimpleLoader();context.setLoader(loader);// 添加servlet访问路径（资源路径） 和 资源名称的映射关系// context.addServletMapping(pattern, name);context.addServletMapping("/Primitive", "Primitive");context.addServletMapping("/Modern", "Modern");connector.setContainer(context);try {connector.initialize(); // 初始化，主要返回服务器套接字// 触发生命周期事件（可以参考下面的测试用例调用过程示例图）((Lifecycle) connector).start(); // highlight line.((Lifecycle) context).start(); // highlight line.// make the application wait until we press a key.System.in.read();((Lifecycle) context).stop(); // highlight line.}catch (Exception e) {e.printStackTrace();}/* try { // these are some code in tomcat(5)-servlet container.connector.initialize();connector.start();// make the application wait until we press a key.System.in.read();}*/}
}

E:\bench-cluster\cloud-data-preprocess\HowTomcatWorks\src>java -cp .;lib/servlet.jar;lib/catalina_4_1_24.jar;E:\bench-cluster\cloud-data-preprocess\HowTomcatWorks\webroot com.tomcat.chapter6.startup.B ootstrap 
HttpConnector Opening server socket on all host IP addresses
HttpConnector[8080] Starting background thread
SimpleContextLifecycleListener's event before_start
Starting SimpleLoader
Starting Wrapper Primitive
Starting Wrapper Modern
SimpleContextLifecycleListener's event start
Starting context.
SimpleContextLifecycleListener's event after_start
ModernServlet -- init
init
from service
SimpleContextLifecycleListener's event before_stop
SimpleContextLifecycleListener's event stop
Stopping context.
Stopping wrapper Primitive
destroy