How can I make command line interface (CLI)

[Vikas Kumar Sahu]

Hi All,
How can I make command line interface ( CLI ) In Java using JTextArea or JTextField.
Thanks In advance..
Vikas Sahu

[Eddie Vanda]

Hi Vikas,
Someone may already have done this work, but I just played with a JTextArea and a document listener just to see what that's all about.

import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import java.awt.*;
import java.awt.event.*;
public class CLI extends JFrame {
  JTextArea ta = new JTextArea (20,6);
  Document document = ta.getDocument ();
  public static void main (String [] args) {
    CLI cli = new CLI ();
  }
  CLI () {
    ta.setText ("First Line\nSecond Line\nThird Line");
    Container c = getContentPane ();
    c.add (ta);
    document.addDocumentListener (new DocumentListener () {
      public void changedUpdate(DocumentEvent e) {
        doCLI (e);
      }
      public void removeUpdate(DocumentEvent e) {
        doCLI (e);
      }
      public void insertUpdate(DocumentEvent e) {
        doCLI (e);
      }
    });
    setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
    setBounds (10,10, 300, 300);
    setVisible (true);
  }
  void doCLI (DocumentEvent e) {
    Element elem = null;
     System.out.println ("doCLI getLength " + e.getLength() );
              //Returns the length of the change.
     System.out.println ("doCLI getOffset " + e.getOffset() );
              //Returns the offset within the document of the start of the change.
     System.out.println ("doCLI getType " + e.getType ());
  }
}

I found it interesting to highlight a bit of code and then paste a letter to replace that highlighted area. You could combine that with ta.getText() to see what cli input was made when the last character is a cr.
Ed