1.首先：org.apache.catalina.connector.http.HttpConnector作为守护线程启动之
前，创建一个了Stack(org.apache.catalina.connector.http.HttpProcessor)用来准备
处理Socket。
HttpConnector的Start()方法：
public void start() throws LifecycleException {
// Validate and update our current state
if (started)
throw new LifecycleException
(sm.getString("httpConnector.alreadyStarted"));
threadName = "HttpConnector[" + port + "]";
lifecycle.fireLifecycleEvent(START_EVENT, null);
started = true;
// Start our background thread
//--------------------启动HttpConnector run() begin----------------
threadStart();//见下方run()方法
//--------------------启动HttpConnector run() end------------------
// Create the specified minimum number of processors
while (curProcessors < minProcessors) {
if ((maxProcessors > 0) && (curProcessors >= maxProcessors))
break;
//------------------------创建线程池begin-------------------------
HttpProcessor processor = newProcessor();//见下方
//------------------------创建线程池end------------------------------
recycle(processor);
}
}
HttpConnector的run()方法
public void run() {
// Loop until we receive a shutdown command
while (!stopped) {
// Accept the next incoming connection from the server socket
Socket socket = null;
try {
socket = serverSocket.accept();
if (connectionTimeout > 0)
socket.setSoTimeout(connectionTimeout);
socket.setTcpNoDelay(tcpNoDelay);
} catch (AccessControlException ace) {
log("socket accept security exception", ace);
continue;
} catch (IOException e) {
try {
//If reopening fails, exit
synchronized (threadSync) {
if (started && !stopped)
log("accept error: ", e);
if (!stopped) {osing server socket");
serverSocket.close();
serverSocket = open();
}
}
} catch (IOException ioe) {
log("socket reopen, io problem: ", ioe);
break;
} catch (KeyStoreException kse) {
log("socket reopen, keystore problem: ", kse);
break;
} catch (NoSuchAlgorithmException nsae) {
log("socket reopen, keystore algorithm problem: ", nsae);
break;
} catch (CertificateException ce) {
log("socket reopen, certificate problem: ", ce);
break;
} catch (UnrecoverableKeyException uke) {
log("socket reopen, unrecoverable key: ", uke);
break;
} catch (KeyManagementException kme) {
log("socket reopen, key management problem: ", kme);
break;
}
continue;
}
// Hand this socket off to an appropriate processor
HttpProcessor processor = createProcessor();
if (processor == null) {
try {
log(sm.getString("httpConnector.noProcessor"));
socket.close();
} catch (IOException e) {
;
}
continue;
}
//触发条件启动org.apache.catalina.connector.http.HttpProcessor begin
processor.assign(socket);//见下方assign方法
//触发条件启动org.apache.catalina.connector.http.HttpProcessor end
// The processor will recycle itself when it finishes
}
// Notify the threadStop() method that we have shut ourselves down
synchronized (threadSync) {
threadSync.notifyAll();
}
}
newProcessor()方法：
private HttpProcessor newProcessor() {
// if (debug >= 2)
// log("newProcessor: Creating new processor");
HttpProcessor processor = new HttpProcessor(this, curProcessors++);
if (processor instanceof Lifecycle) {
try {
((Lifecycle) processor).start();
} catch (LifecycleException e) {
log("newProcessor", e);
return (null);
}
}
created.addElement(processor);
return (processor);
}
HttpProcessor的assign(Socket socket)方法：
synchronized void assign(Socket socket) {
//----------------问题所在地 begin-----------------
// Wait for the Processor to get the previous Socket
while (available) {
try {
wait();
} catch (InterruptedException e) {
}
}
//----------------问题所在地 end-----------------
// Store the newly available Socket and notify our thread
this.socket = socket;
available = true;
notifyAll();
if ((debug >= 1) && (socket != null))
log(" An incoming request is being assigned");
}
2.问题：我理解：明明在run()方法中，每个socket请求都会对应从professor池子里面找一个新的HttpProcessor出来。此时该HttpProcessor既然已经在池子里就一定是available=false的。那么就不可能在assign方法中出现available=true的情况。如果真是这样那么这段代码不就没有意义了么？还是我的理解有问题？
在HttpProcessor中有可能出现available=true然后又在assign()方法中接收socket的情况吗？
源码贴不上来，有需要可以邮件发送该tomcat对应完整源码
