Java Code:
import java.awt.AWTEventMulticaster;
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.JFrame;
import javax.swing.JTextField;

public class KeyTextTester {
  public static void main(String args[]) {
    JFrame frame = new JFrame("Key Text Sample");
    KeyTextComponent keyTextComponent = new KeyTextComponent();
    final JTextField textField = new JTextField();

    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
        String keyText = actionEvent.getActionCommand();
        textField.setText(keyText);
      }
    };
    keyTextComponent.addActionListener(actionListener);

    Container contentPane = frame.getContentPane();
    contentPane.add(keyTextComponent, BorderLayout.CENTER);
    contentPane.add(textField, BorderLayout.SOUTH);
    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}

class KeyTextComponent extends Canvas {
  private ActionListener actionListenerList = null;

  public KeyTextComponent() {
    setBackground(Color.cyan);
    KeyListener internalKeyListener = new KeyAdapter() {
      public void keyPressed(KeyEvent keyEvent) {
        if (actionListenerList != null) {
          int keyCode = keyEvent.getKeyCode();
          String keyText = KeyEvent.getKeyText(keyCode);
          ActionEvent actionEvent = new ActionEvent(this,
              ActionEvent.ACTION_PERFORMED, keyText);
          actionListenerList.actionPerformed(actionEvent);
        }
      }
    };

    MouseListener internalMouseListener = new MouseAdapter() {
      public void mousePressed(MouseEvent mouseEvent) {
        requestFocus();
      }
    };

    addKeyListener(internalKeyListener);
    addMouseListener(internalMouseListener);
  }

  public void addActionListener(ActionListener actionListener) {
    actionListenerList = AWTEventMulticaster.add(actionListenerList,
        actionListener);
  }

  public void removeActionListener(ActionListener actionListener) {
    actionListenerList = AWTEventMulticaster.remove(actionListenerList,
        actionListener);
  }

  public boolean isFocusTraversable() {
    return true;
  }
}