Windows cmd-output (Java)

Question

I've found this topic, but the code doesn't work for me... Return Windows cmd text from Java?

After pressing a button I want to execute a batch-file, for testing purposes it's just the ipconfig-command.

The cmd-output should be written into a JTextFiled, but all I get is no text...

Here the code for writing it into the JTextField:

btnLock.addActionListener(new ActionListener() 
    {
        public void actionPerformed(ActionEvent e) 
        {       
            String g = "";
            try {
                Runtime.getRuntime().exec(new String[] {"ipconfig", g});
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }  
            Process p = null;
            try {
                p = Runtime.getRuntime().exec(new String[] {"ipconfig", g});
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            InputStream s = p.getInputStream();

            BufferedReader in = new BufferedReader(new InputStreamReader(s));
            String temp;

            try {
                while ((temp = in.readLine()) != null) 
                {
                    System.out.println(temp);
                }
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
        }

    });
    btnLock.setBounds(10, 68, 89, 23);
    contentPane.add(btnLock);

So what do I do wrong?

It's my first project with cmd-input, so please don't get mad cause of silly mistakes I made. ;)

Thx

Roddy of the Frozen Peas · Accepted Answer · 2012-08-02 15:46:15Z

3

Try the exec command that just takes a String parameter. The following test code worked on my system (though I was only printing to console, not to textfield):

BufferedReader in = null;
try{
    Process p = Runtime.getRuntime().exec("ipconfig");
    InputStream s = p.getInputStream();

    in = new BufferedReader(new InputStreamReader(s));
    String temp;

    while ((temp = in.readLine()) != null) {
        System.out.println(temp);
    }
} catch (Exception e){
    e.printStackTrace();
} finally {
    if (in != null) in.close();
}

Also your code in the original post is also using a System.out.println. As far as I'm aware, you can't print to a JTextField using System.out.println.... You'd have to use the setText method.

answered Aug 2, 2012 at 15:46

Roddy of the Frozen Peas

15.3k11 gold badges63 silver badges111 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

user1318160 Over a year ago

Ok, it works fine with a non-gui-application. But if I try it with my GUI (and a JTextArea) the output is only the last line...

Roddy of the Frozen Peas Over a year ago

Well yes. It's in a while loop. You'll want to do something like String outpt = ""; while( (temp = ...)) { outpt += temp + "\n"; } textField.setText(outpt);

Peter Lawrey · Accepted Answer · 2012-08-02 15:34:32Z

3

If I run

 ipconfig ""

I get

** Error: unrecognized or incomplete command line.**

You can only run from Java, commands which work on the command line.

BTW: If you are looking for errors, you need to read the error stream.

answered Aug 2, 2012 at 15:34

Peter Lawrey

535k83 gold badges770 silver badges1.2k bronze badges

4 Comments

user1318160 Over a year ago

Thx, I'm new to Java, so please excuse, but what does "commands which work on the command line" mean? Why does ipconfig not work on the command line?

Roddy of the Frozen Peas Over a year ago

Explicitly, ipconfig "" does not work on the commandline. ipconfig does.

Peter Lawrey Over a year ago

@user1318160 I suggest you try it on the command line for yourself. ;)

user1318160 Over a year ago

Oh, I didn't notice the "" , sorry!

Oday Mansour · Accepted Answer · 2012-08-02 15:35:31Z

1

I would Runtime.getRuntime().exec(new String[] {"ipconfig > temp.txt"}); and then just read it as a text file using a BufferedReader.

I hope this helps.

answered Aug 2, 2012 at 15:35

Oday Mansour

2441 silver badge12 bronze badges

2 Comments

user1318160 Over a year ago

Do you have the whole code? I tried to do it, but I only get: Error: unrecognized or incomplete command line.

user1318160 Over a year ago

Ok, I used Roddy of the Frozen Pea's solution, works flawlessly.

Collectives™ on Stack Overflow

Windows cmd-output (Java)

3 Answers 3

2 Comments

4 Comments

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

4 Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related