commandrunner.java

java写的用于远程执行程序的shell程序

import java.net.*;
import java.io.*;
import java.util.*;


class CommandRunner implements Runnable
{
	static String m_strFilter = "";
	Socket m_sock;	
	final public void run()
	{
		try
		{
			// get the ip address of the client
			String strClient = m_sock.getInetAddress().toString();
			// exit the thread if client ip address does not have 
			// permission to access this server
			// (you can add more complicated security here)
			if(!m_strFilter.equals("")&&strClient.indexOf(m_strFilter)<0)
			{
				m_sock.close();
				System.out.println("Connection closed: "+strClient);	
				return;
			}
			// open input and output streams to the client
			BufferedInputStream inStream = new BufferedInputStream(m_sock.getInputStream());
			BufferedOutputStream outStream = new BufferedOutputStream(m_sock.getOutputStream());
			try
			{
				while(true)
				{
					// receive the command from the client
					byte[] pCommand = SockData.Read(inStream);
					// end the thread if no command is received
					if(pCommand.length==0) return;
					// receive the input to the command from the client
					byte[] pInput = SockData.Read(inStream);
					// print what has been received from the client
					System.out.print("Client '"+strClient+"' executed command '"+new String(pCommand)+"' with input '"+new String(pInput)+"'\r\n");
					// create a process for the command
					Process proc = Runtime.getRuntime().exec(new String(pCommand),null);
					// write the input to the created process
					if(pInput.length>0)
					{
						BufferedOutputStream out = new BufferedOutputStream(proc.getOutputStream());
						out.write(pInput);
						out.write("\r\n".getBytes());
						out.close();
					}
					// open output and error streams of the created process
					BufferedInputStream in = new BufferedInputStream(proc.getInputStream());
					BufferedInputStream err = new BufferedInputStream(proc.getErrorStream());
					// send output and error from the created process to client
					int nOut = 0;
					int nErr = 0;
					int nSize = 64*1024;
					byte[] pBuffer = new byte[nSize];
					while(nOut>=0||nErr>=0)
					{
						// read and send normal output
						nOut = in.read(pBuffer,0,nSize);
						while(nOut>0) 
						{
							SockData.Write(outStream,pBuffer,nOut);
							Thread.currentThread().sleep(100);
							nOut = in.read(pBuffer,0,nSize);
						}
						// read and send error output
						nErr = err.read(pBuffer,0,nSize);
						while(nErr>0) 
						{
							SockData.Write(outStream,pBuffer,nOut);
							Thread.currentThread().sleep(100);
							nErr = err.read(pBuffer,0,nSize);
						}
						// sleep a while to avoid burning too much CPU
						Thread.currentThread().sleep(100);
					}
					// write end of output data
					SockData.Write(outStream,null,0);	
					// clean up
					in.close();
					err.close();
					proc.destroy();
				}
			}
			catch(Exception e)
			{
				// send exception info to client
				byte[] pError = (e.getMessage()+"\r\n").getBytes(); 
				SockData.Write(outStream,pError,pError.length);
				// write end of output data
				SockData.Write(outStream,null,0);	
			}
			// close connection to client
			outStream.close();
			inStream.close();	
			m_sock.close();
		}
		catch(Exception e)
		{
			System.out.println(e.getMessage());
		}
	}	
}