tomcat解析(十)StandardService.initialize.start

先上代碼:
一.initialize
 /** * Invoke a pre-startup initialization. This is used to allow connectors * to bind to restricted ports under Unix operating environments. */ public void initialize() throws LifecycleException { // Service shouldn't be used with embeded, so it doesn't matter if (initialized) { if(log.isInfoEnabled()) log.info(sm.getString("standardService.initialize.initialized")); return; } initialized = true; if( oname==null ) { try { // Hack - Server should be deprecated... Container engine=this.getContainer(); domain=engine.getName(); oname=new ObjectName(domain + ":type=Service,serviceName="+name); this.controller=oname; Registry.getRegistry(null, null) .registerComponent(this, oname, null); Executor[] executors = findExecutors(); for (int i = 0; i < executors.length; i++) { ObjectName executorObjectName = new ObjectName(domain + ":type=Executor,name=" + executors[i].getName()); Registry.getRegistry(null, null) .registerComponent(executors[i], executorObjectName, null); } } catch (Exception e) { log.error(sm.getString("standardService.register.failed",domain),e); } } if( server==null ) { // Register with the server // HACK: ServerFactory should be removed... ServerFactory.getServer().addService(this); } // Initialize our defined Connectors synchronized (connectors) { for (int i = 0; i < connectors.length; i++) { connectors[i].initialize(); } } }

主要的內容有三部分:
1.Registry.getRegistry(null, null).registerComponent(executors[i], executorObjectName, null);
 使用MBean註冊組件
2.ServerFactory.getServer().addService(this);
 ServerFactory.getServer()返回的對象爲StandardServer對象,而在實例化StandardService時已經調用了該方法進行設置了,因此這裏其它是做多了一次設置
3.connectors[i].initialize();
 分別調用所有connectors的initialize()方法,該方法如下:
 /** * Initialize this connector (create ServerSocket here!) */ public void initialize() throws LifecycleException { if (initialized) { if(log.isInfoEnabled()) log.info(sm.getString("coyoteConnector.alreadyInitialized")); return; } this.initialized = true; if( oname == null && (container instanceof StandardEngine)) { try { // we are loaded directly, via API - and no name was given to us StandardEngine cb=(StandardEngine)container; oname = createObjectName(cb.getName(), "Connector"); Registry.getRegistry(null, null) .registerComponent(this, oname, null); controller=oname; } catch (Exception e) { log.error( "Error registering connector ", e); } if(log.isDebugEnabled()) log.debug("Creating name for connector " + oname); } // Initializa adapter adapter = new CoyoteAdapter(this); protocolHandler.setAdapter(adapter); IntrospectionUtils.setProperty(protocolHandler, "jkHome", System.getProperty("catalina.base")); try { protocolHandler.init(); } catch (Exception e) { throw new LifecycleException (sm.getString ("coyoteConnector.protocolHandlerInitializationFailed", e)); } }

可看到實例化了adapter對象後,最終調用了protocolHandler.init(),其中protocolHandler對象實例化過程如下:
 /** * Coyote Protocol handler class name. * Defaults to the Coyote HTTP/1.1 protocolHandler. */ protected String protocolHandlerClassName = "org.apache.coyote.http11.Http11Protocol"; ...... public Connector(String protocol) throws Exception { setProtocol(protocol); // Instantiate protocol handler try { Class clazz = Class.forName(protocolHandlerClassName); this.protocolHandler = (ProtocolHandler) clazz.newInstance(); } catch (Exception e) { log.error (sm.getString ("coyoteConnector.protocolHandlerInstantiationFailed", e)); } }

因此這裏將調用的是Http11Protocol的方法 ，我們再看Http11Protocol.init到底做了什麼事
 protected Http11ConnectionHandler cHandler = new Http11ConnectionHandler(this); protected JIoEndpoint endpoint = new JIoEndpoint(); ...... public void init() throws Exception { endpoint.setName(getName()); endpoint.setHandler(cHandler); // Verify the validity of the configured socket factory try { if (isSSLEnabled()) { sslImplementation = SSLImplementation.getInstance(sslImplementationName); socketFactory = sslImplementation.getServerSocketFactory(); endpoint.setServerSocketFactory(socketFactory); } else if (socketFactoryName != null) { socketFactory = (ServerSocketFactory) Class.forName(socketFactoryName).newInstance(); endpoint.setServerSocketFactory(socketFactory); } } catch (Exception ex) { log.error(sm.getString("http11protocol.socketfactory.initerror"), ex); throw ex; } if (socketFactory!=null) { Iterator<String> attE = attributes.keySet().iterator(); while( attE.hasNext() ) { String key = attE.next(); Object v=attributes.get(key); socketFactory.setAttribute(key, v); } } try { endpoint.init(); } catch (Exception ex) { log.error(sm.getString("http11protocol.endpoint.initerror"), ex); throw ex; } if (log.isInfoEnabled()) log.info(sm.getString("http11protocol.init", getName())); }  

    前一部分是在設置endpoint對象的屬性,最後調用其Init方法,如下:
    public void init() throws Exception { if (initialized) return; // Initialize thread count defaults for acceptor if (acceptorThreadCount == 0) { acceptorThreadCount = 1; } if (serverSocketFactory == null) { serverSocketFactory = ServerSocketFactory.getDefault(); } if (serverSocket == null) { try { if (address == null) { serverSocket = serverSocketFactory.createSocket(port, backlog); } else { serverSocket = serverSocketFactory.createSocket(port, backlog, address); } } catch (BindException be) { if (address == null) throw new BindException(be.getMessage() + "<null>:" + port); else throw new BindException(be.getMessage() + " " + address.toString() + ":" + port); } } //if( serverTimeout >= 0 ) // serverSocket.setSoTimeout( serverTimeout ); initialized = true; }  

    最終產生了一個ServerSocket對象,雖然有ServerSocket,但還需要執行其accept()才能獲取客戶端請求的,因此這裏其實還不能處理請求.
二.start
 /** * Prepare for the beginning of active use of the public methods of this * component. This method should be called before any of the public * methods of this component are utilized. It should also send a * LifecycleEvent of type START_EVENT to any registered listeners. * * @exception LifecycleException if this component detects a fatal error * that prevents this component from being used */ public void start() throws LifecycleException { // Validate and update our current component state if (log.isInfoEnabled() && started) { log.info(sm.getString("standardService.start.started")); } if( ! initialized ) init(); // Notify our interested LifecycleListeners lifecycle.fireLifecycleEvent(BEFORE_START_EVENT, null); if(log.isInfoEnabled()) log.info(sm.getString("standardService.start.name", this.name)); lifecycle.fireLifecycleEvent(START_EVENT, null); started = true; // Start our defined Container first if (container != null) { synchronized (container) { if (container instanceof Lifecycle) { ((Lifecycle) container).start(); } } } synchronized (executors) { for ( int i=0; i<executors.size(); i++ ) { executors.get(i).start(); } } // Start our defined Connectors second synchronized (connectors) { for (int i = 0; i < connectors.length; i++) { if (connectors[i] instanceof Lifecycle) ((Lifecycle) connectors[i]).start(); } } // Notify our interested LifecycleListeners lifecycle.fireLifecycleEvent(AFTER_START_EVENT, null); }

主要的內容有二部分:
1.lifecycle.fireLifecycleEvent
 觸發Lifecycle事件,這裏沒有註冊相應的監聽器
2.((Lifecycle) container).start();executors.get(i).start();((Lifecycle) connectors[i]).start();
調用了幾元素的start方法

這裏的container,executors及connectors從何而來呢?
1.executors是需要在server.xml裏配置Server/Service/Executor的,如果進行了配置,將產生類型爲org.apache.catalina.core.StandardThreadExecutor的對象,並全部放入StandardService的ArrayList<Executor> executors裏
2.connectors與executors一樣，也要進行配置,路徑爲Server/Service/Connector,對象類型爲:org.apache.catalina.connector.Connector
3.container則需要查看Catalina.createStartDigester裏的內容,有一句代碼如下:
 digester.addRuleSet(new EngineRuleSet("Server/Service/"));
查看EngineRuleSet對象addRuleInstances方法,可看到將添加ObjectCreateRule創建類型爲org.apache.catalina.core.StandardEngine的對象,並調用StandardService.setContainer,對象將放入StandardService的container變量裏,同時放入Connector的container變量,而該StandardService對象將放入StandardEngine的service變量裏,因此這裏將調用StandardEngine.start();
這裏需要注意的是container.start的調用是在Connector之前的,這樣做是有理由的;container.start()裏將會爲服務器準備所有工程項目的解析及部署工作,而Connector.start()將會讓tomcat開始接受並處理用戶的請求,因此是需要放在工程部署準備完成之後的,因此Connector.start()我們將放在最後來講,下一篇目我們講的是StandardEngine