tomcat源码分析 Acceptor run 过程

nmkl

　　org.apache.tomcat.util.net.JIoEndpoint.Acceptor
　　1、调用countUpOrAwaitConnection，阀门数加1。
　　每个Acceptor有最大处理上限，默认为10000，如为-1，则无上限。
　　



protected void countUpOrAwaitConnection() throws InterruptedException {
if (maxConnections==-1) return;
LimitLatch latch = connectionLimitLatch;
if (latch!=null) latch.countUpOrAwait();
}
　　
　　2、默认serverSocket监听8080端口，当监听到请求时，为socket设置默认的options。



protected boolean setSocketOptions(Socket socket) {
try {
// 1: Set socket options: timeout, linger, etc
            socketProperties.setProperties(socket);
} catch (SocketException s) {
//error here is common if the client has reset the connection
if (log.isDebugEnabled()) {
log.debug(sm.getString("endpoint.err.unexpected"), s);
}
// Close the socket
return false;
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
log.error(sm.getString("endpoint.err.unexpected"), t);
// Close the socket
return false;
}
return true;
}
　　
　　3、为其生成一个包装器类，SocketWrapper，除socket属性之外，还包括其它一些属性
　　如：lastAccess， timeout，async
　　4、为包装器类生成一个SocketProcessor类，这个类实现了Runnable接口，并将此实例添加到线程队列中，交由线程池处理。



protected boolean processSocket(Socket socket) {
// Process the request from this socket
try {
SocketWrapper<Socket> wrapper = new SocketWrapper<Socket>(socket);
wrapper.setKeepAliveLeft(getMaxKeepAliveRequests());
// During shutdown, executor may be null - avoid NPE
if (!running) {
return false;
}
getExecutor().execute(new SocketProcessor(wrapper));
} catch (RejectedExecutionException x) {
log.warn("Socket processing request was rejected for:"+socket,x);
return false;
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
// This means we got an OOM or similar creating a thread, or that
// the pool and its queue are full
log.error(sm.getString("endpoint.process.fail"), t);
return false;
}
return true;
}
　　
　　5、阀门数减1.



protected long countDownConnection() {
if (maxConnections==-1) return -1;
LimitLatch latch = connectionLimitLatch;
if (latch!=null) {
long result = latch.countDown();
if (result<0) {
getLog().warn("Incorrect connection count, multiple socket.close called on the same socket." );
}
return result;
} else return -1;
}