Apache DefaultExecutor and Ping command for JTextArea

Question

I am a newbie in Java with Apache utilities.

I am studying Apache's DefaultExecutor method with the following code.

---

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import org.apache.commons.exec.CommandLine;
import org.apache.commons.exec.DefaultExecuteResultHandler;
import org.apache.commons.exec.DefaultExecutor;
import org.apache.commons.exec.ExecuteException;
import org.apache.commons.exec.LogOutputStream;
import org.apache.commons.exec.PumpStreamHandler;

public class PingExampleApacheExec {

    public static void main(String[] args) {
        //  
        CommandLine commandLine = new CommandLine("ping");
        commandLine.addArgument("/n");
        commandLine.addArgument("5");
        commandLine.addArguments("/w 1000");
        commandLine.addArgument("127.0.0.1");

        // Executor
        DefaultExecutor executor = new DefaultExecutor();
        try {


            // LogOutputStream 
            LogOutputStream output = new LogOutputStream() {
                @Override
                protected void processLine(String line, int level) {

           //         NewJFrame1 myLOG = new NewJFrame1();   // not worked
           //         myLOG.mainLOG();                       // not worked
           //         myLOG.jTextArea1.setText(line);        // not worked
                      System.out.println(line);
                }
            };
            PumpStreamHandler streamHandler = new PumpStreamHandler(output);
            executor.setStreamHandler(streamHandler);


            executor.setExitValue(0);


            DefaultExecuteResultHandler resultHandler = new DefaultExecuteResultHandler();
            executor.execute(commandLine, resultHandler);

            // TODO output.close() 

        } catch (ExecuteException ex) {
            ex.printStackTrace();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
}

==========================

My simple question: The above code is simply working, but it failed when I redirect the string to a JTextArea.

How can we do it? i.e. how to print the ping info into a JTextArea? Why SetText/append didn't work?

Answer 1

I see that setText() and append() are no longer thread-safe since Java 7.