Telnet关闭Tomcat

佚名 6年前 (2019-04-21) 随笔 1794人围观抢沙发百度已收录

web.xml 中默认配置

<Server port="8005" shutdown="SHUTDOWN"></Server>

操作步骤

telnet 127.0.0.1 8005
发送【SHUTDOWN】，会发现Tomcat关闭

说明

private volatile boolean stopAwait = false;
@Override
public void await() {
    // 端口设置为 -2， tomcat启动失败
    if( port == -2 ) {
        return;
    }
    // 端口设置为 -1，休眠 10s，重新检测
    if( port==-1 ) {
        try {
            awaitThread = Thread.currentThread();
            while(!stopAwait) {
                try {
                    Thread.sleep( 10000 );
                } catch( InterruptedException ex ) {
                }
            }
        } finally {
            awaitThread = null;
        }
        return;
    }

    // 监听默认设置 端口
    try {
        awaitSocket = new ServerSocket(port, 1,
                                       InetAddress.getByName(address));
    } catch (IOException e) {
        return;
    }

    try {
        awaitThread = Thread.currentThread();

        // Loop waiting for a connection and a valid command
        while (!stopAwait) {
            ServerSocket serverSocket = awaitSocket;
            if (serverSocket == null) {
                break;
            }

            // Wait for the next connection
            Socket socket = null;
            StringBuilder command = new StringBuilder();
            try {
                InputStream stream;
                long acceptStartTime = System.currentTimeMillis();
                try {
                    socket = serverSocket.accept();
                    socket.setSoTimeout(10 * 1000);  // Ten seconds
                    stream = socket.getInputStream();
                } catch (SocketTimeoutException ste) {
                    continue;
                } catch (AccessControlException ace) {
                    continue;
                } catch (IOException e) {
                    if (stopAwait) {
                        break;
                    }
                    break;
                }

                // Read a set of characters from the socket
                int expected = 1024; // Cut off to avoid DoS attack
                while (expected < shutdown.length()) {
                    if (random == null)
                        random = new Random();
                    expected += (random.nextInt() % 1024);
                }
                while (expected > 0) {
                    int ch = -1;
                    try {
                        ch = stream.read();
                    } catch (IOException e) {
                        ch = -1;
                    }
                    // Control character or EOF (-1) terminates loop
                    if (ch < 32 || ch == 127) {
                        break;
                    }
                    command.append((char) ch);
                    expected--;
                }
            } finally {
                if (socket != null) {
                    socket.close();
                }
            }

            // 接收的命令 == 设置的关闭指令
            boolean match = command.toString().equals(shutdown);
            if (match) {
                break;
            } else
                log.warn("StandardServer.await: Invalid command '"
                         + command.toString() + "' received");
        }
    } finally {
        ServerSocket serverSocket = awaitSocket;
        awaitThread = null;
        awaitSocket = null;

        // Close the server socket and return
        if (serverSocket != null) {
            try {
                serverSocket.close();
            } catch (IOException e) {
                // Ignore
            }
        }
    }
}