Ho copiincollato pari pari il tuo codice in un programma scritto 100% col blocco note...

codice:
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

public class SpostaLabel extends JFrame implements MouseListener {
   private JLabel jLabel1;
   private JLabel jLabel5;

   public SpostaLabel() {
      Container c = getContentPane();
      c.setLayout( null );

      jLabel1 = new JLabel("Label 1");
      jLabel1.setBounds(10, 10, 130, 18);
      jLabel1.addMouseListener( this );

      jLabel5 = new JLabel("5");
      jLabel5.setBounds(10, 100, 130, 18);

      c.add( jLabel1 );
      c.add( jLabel5 );

      setTitle("Sposta Label");
      setSize(800, 600);
      setDefaultCloseOperation( EXIT_ON_CLOSE );
      setVisible( true );
   }

   public void mouseExited(MouseEvent me) { }
   public void mouseClicked(MouseEvent me) { }
   public void mousePressed(MouseEvent me) { }
   public void mouseReleased(MouseEvent me) { }

   public void mouseEntered(MouseEvent evt) {                                     
      int randomx, randomy, randomex, prex, prey;
      prey = jLabel1.getY();
      prex = jLabel1.getX();    
      do randomx = (int)(Math.random() * 1000);
      while (randomx >= 350);
      do randomy = (int)(Math.random() * 1000);    
      while (randomy >= 350);
      if ((randomy >= 500) && (randomx >= 500)) {
         randomy = 100;randomx = 150;
      }
      jLabel1.setBounds(randomx, randomy, 130, 18);
      jLabel5.setText(String.valueOf(Integer.parseInt(jLabel5.getText())+1));

      randomx = randomy = 401;
   }
   public static void main(String[] args) {
      SpostaLabel sl = new SpostaLabel();
   }
}
Ora, a te capire perchè quello scritto 75% ide non funziona, quello scritto 100% uomo non ha problemi.


Ciao.