打开命令行+ GUI输入

Question

I am trying to write a java GUI in netbeans for executing a program on the command line, and currently have this piece of code assigned to a button

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    try
        {
        Runtime rt = Runtime.getRuntime();
            Process pr = rt.exec("open -a /Applications/Utilities/Terminal.app");


            BufferedReader input = new BufferedReader(new InputStreamReader(pr.getInputStream()));

            String line=null;

            while((line=input.readLine()) != null)
            {
            System.out.println(line);
            }

            int exitVal = pr.waitFor();
            System.out.println("Exited with error code "+exitVal);
            } 
     catch(Exception e)
            {
            System.out.println(e.toString());
            e.printStackTrace();
            }
}

This opens the terminal, however I would like to know how I should go about inputting commands into the terminal while still just pressing the button (ex: "ls", "cd", "javac" etc) Thanks!

UPDATE: @Codebender My code now looks like this.

Runtime rt = Runtime.getRuntime();
    Process pr = rt.exec("open -a /Applications/Utilities/Terminal.app");
            new PrintStream(pr.getOutputStream).println("ls");

I am getting the error "cannot find symbol, symbol: variable getOutputStream, location: variable pr of type process" and a red line under getOutputStream. Any ideas?

@Codebender So should it be like this?

new PrintStream(pr.getOutputStream{println("ls")});

Answer 1

Use can use outputStream to write to the terminal. Wrap it up with a printstream to make things easier.

Process pr = rt.exec("open -a /Applications/Utilities/Terminal.app");
PrintStream ps = new PrintStream(pr.getOutputStream());
ps.println("ls" + System.lineSeparator());
// Follow with the reading of output from terminal.

If your Terminal.app is the default linux terminal, instead of opening a new one you can try,

Process pr = rt.exec("ls");
// Follow with the reading of output.