关于Java钩子的使用

package test;

import java.io.FileWriter;
import java.io.IOException;
import java.util.Date;

public class Untitled1 {

	public Untitled1(){
		doShutDownWork();
		
	}
	private void doShutDownWork(){
		Runtime.getRuntime().addShutdownHook(new Thread()
		{
			public void run(){
				try{
					FileWriter fw=new FileWriter("c:\\t.log");
					System.out.println("Im going to end");
					fw.write("The application ended! "+(new Date()).toString());
					fw.close();
				}catch(IOException ex){
					
				}
				
			}
			
		});
		
	}
	
	public static void main(String[] args){
		Untitled1 untitled11=new Untitled1();
		long s=System.currentTimeMillis();
		for(int i=0;i<1000000000;i++){
			
		}
		long se=System.currentTimeMillis();
		System.out.println(se-s);
		
	}
}

但是我还是不知道，tomcat是如何退出的，请教各位提提意见，一直想知道。

评论

2 楼 xiegqooo 2012-12-21  

简单的关闭 tomcat

import java.io.IOException;
import java.io.OutputStream;
import java.net.Socket;
import java.net.UnknownHostException;

public class ShutdownService {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		try {
			Socket socket = new Socket("127.0.0.1", 8005);
			OutputStream stream = socket.getOutputStream();
			String shutdown = "SHUTDOWN";
			for (int i = 0; i < shutdown.length(); i++)
				stream.write(shutdown.charAt(i));
			stream.flush();
			stream.close();
			socket.close();
		} catch (UnknownHostException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

}

1 楼 xiegqooo 2012-12-21  

下面是 tomcat 等待关闭的源代码  。 如何有退出 tomcat 。应该会明白的 。

org.apache.catalina.core.StandardServer

int port = 8005;
ServerSocket awaitSocket;

    /**
     * Wait until a proper shutdown command is received, then return.
     * This keeps the main thread alive - the thread pool listening for http 
     * connections is daemon threads.
     */
    public void await() {
        // Negative values - don't wait on port - tomcat is embedded or we just don't like ports
        if( port == -2 ) {
            // undocumented yet - for embedding apps that are around, alive.
            return;
        }
        if( port==-1 ) {
            try {
                awaitThread = Thread.currentThread();
                while(!stopAwait) {
                    try {
                        Thread.sleep( 10000 );
                    } catch( InterruptedException ex ) {
                        // continue and check the flag
                    }
                }
            } finally {
                awaitThread = null;
            }
            return;
        }
        
        // Set up a server socket to wait on
        try {
            awaitSocket =
                new ServerSocket(port, 1,
                                 InetAddress.getByName("localhost"));
        } catch (IOException e) {
            log.error("StandardServer.await: create[" + port
                               + "]: ", 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 = null;
                    try {
                        socket = serverSocket.accept();
                        socket.setSoTimeout(10 * 1000);  // Ten seconds
                        stream = socket.getInputStream();
                    } catch (AccessControlException ace) {
                        log.warn("StandardServer.accept security exception: "
                                           + ace.getMessage(), ace);
                        continue;
                    } catch (IOException e) {
                        if (stopAwait) {
                            // Wait was aborted with socket.close()
                            break;
                        }
                        log.error("StandardServer.await: accept: ", e);
                        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) {
                            log.warn("StandardServer.await: read: ", e);
                            ch = -1;
                        }
                        if (ch < 32)  // Control character or EOF terminates loop
                            break;
                        command.append((char) ch);
                        expected--;
                    }
                } finally {
                    // Close the socket now that we are done with it
                    try {
                        if (socket != null) {
                            socket.close();
                        }
                    } catch (IOException e) {
                        // Ignore
                    }
                }

                // Match against our command string
                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
                }
            }
        }
    }