无法调用Runtime.getRuntime（）。exec

Question

我正在运行一个xSocket服务器，因此需要启动一个chat.jar，它似乎没有调用该部分。我的代码有什么问题？

如果我创建了一个xSocketserver.jar，那么exec是否可以启动任何外部jar？

import java.io.*; 
import org.xsocket.connection.*; 

public class xSocketServer 
{ 
    protected static IServer srv = null; 

    public static void main(String[] args) 
    { 
     try { 
      srv = new Server("127.0.0.1",8090, new xSocketDataHandler()); 
      srv.run(); 
     } 
     catch(Exception ex) { 
      System.out.println(ex.getMessage()); 
     } 

     try { 
      System.out.println("setup exec"); 
      Process p = Runtime.getRuntime().exec("cmd java -jar D:\\chat.jar -n 0"); 
      p.waitFor(); 
      System.out.println("call exec"); 
     } 
     catch(Exception ex) { 
      System.out.println(ex.getMessage()); 
     } 
    } 

    protected static void shutdownServer() { 
     try { 
      srv.close(); 
     } 
     catch(Exception ex) { 
      System.out.println(ex.getMessage()); 
     } 
    } 
} 

Answer 1

您应该阅读过程的输出流和errorstream。您的命令可能失败，并且您不能看到错误，因为您没有阅读错误流。

看看this article。

Answer 2

1. srv.run（）; - >这个调用不会像xSocket文件那样返回，所以其余代码不会执行。

2. 进程p = Runtime.getRuntime（）。exec（“cmd java -jar D：\ chat.jar -n 0”）;
   你应该调用exec带有参数的阵列是这样的：

   方法P =调用Runtime.getRuntime（）EXEC（新的String [] { “CMD”，“Java的罐子d：\ chat.jar -n 0 “}）;

它会清除程序运行和参数。

Answer 3

也许这是你的意思吗？

public class XServer implements IDataHandler { 

/** 
    * @param args 
    * @throws IOException 
    * @throws UnknownHostException 
    */ 
public static void main(String[] args) throws UnknownHostException, IOException { 
    IServer server = new Server(8090,new XServer()); 
    server.start(); 
} 

@Override 
public boolean onData(INonBlockingConnection nbc) throws IOException, BufferUnderflowException, 
    ClosedChannelException, MaxReadSizeExceededException { 
    String data = nbc.readStringByDelimiter("\r\n"); 
    nbc.write(data + "\r\n"); 

    System.out.println("setup exec"); 
     Process p = Runtime.getRuntime().exec(new String[]{"cmd","java -jar D:\\chat.jar -n 0"}); 
     try { 
    p.waitFor(); 
    } catch (InterruptedException e) { 
    e.printStackTrace(); 
    } 
     System.out.println("call exec"); 


    return true; 
} 

} 

telnet到您的本地端口8090上，输入一行文本和服务器将执行您的聊天程序。

Answer 4

import java.io.IOException; 
import java.nio.BufferUnderflowException; 
import java.nio.channels.ClosedChannelException; 
import java.util.*; 
import org.xsocket.*; 
import org.xsocket.connection.*; 

public class xSocketDataHandler implements IDataHandler, IConnectHandler, IDisconnectHandler 
{ 
    private Set<INonBlockingConnection> sessions = Collections.synchronizedSet(new HashSet<INonBlockingConnection>()); 

    public boolean onData(INonBlockingConnection nbc) throws IOException, BufferUnderflowException, ClosedChannelException, MaxReadSizeExceededException 
    { 
     try 
     { 
      String data = nbc.readStringByDelimiter("\0"); 
      //if(data.trim().length() > 0) 
      //{ 
       //System.out.println("Incoming data: " + data); 

       //nbc.write("+A4\0"); 
       /* 
       if(data.equalsIgnoreCase("<policy-file-request/>")) 
       { 
        nbc.write("<cross-domain-policy><allow-access-from domain=\"*\" to-ports=\"8090\"/></cross-domain-policy>\0"); 
        return true; 
       } 
       */ 
       //String[] message = data.split("~"); 
       String message = data; 
       sendMessageToAll(message); 

       //if(message.equalsIgnoreCase("SHUTDOWN")) 
        // xSocketServer.shutdownServer(); 
      //} 
     } 
     catch(Exception ex) 
     { 
     System.out.println("onData2: " + ex.getMessage()); 
     } 

     return true; 
    } 

    private void sendMessageToAll(String message) 
    { 
     try 
     { 
      synchronized(sessions) 
      { 
       Iterator<INonBlockingConnection> iter = sessions.iterator(); 

       while(iter.hasNext()) 
       { 
        INonBlockingConnection nbConn = (INonBlockingConnection) iter.next(); 

        if(nbConn.isOpen()) 
        nbConn.write(message+"\0"); 
       } 
      } 

      //System.out.println("Outgoing data: " + message); 
     } 
     catch(Exception ex) 
     { 
      System.out.println("sendMessageToAll: " + ex.getMessage()); 
     } 
    } 

    //////////////////////////////////////////////////////////////////////////////////// 
    public boolean onConnect(INonBlockingConnection nbc) throws IOException, BufferUnderflowException, MaxReadSizeExceededException 
    { 
     try 
     { 
      synchronized(sessions) 
      { 
       sessions.add(nbc); 
      } 

      //System.out.println("onConnect"); 
     } 
     catch(Exception ex) 
     { 
      System.out.println("onConnect: " + ex.getMessage()); 
     } 

     return true; 
    } 

    public boolean onDisconnect(INonBlockingConnection nbc) throws IOException 
    { 
     try 
     { 
      synchronized(sessions) 
      { 
       sessions.remove(nbc); 
      } 

      //System.out.println("onDisconnect"); 
     } 
     catch(Exception ex) 
     { 
      System.out.println("onDisconnect: " + ex.getMessage()); 
     } 

     return true; 
    } 
}