import java.awt.*;

import java.awt.event.*;

import java.util.*;

import javax.swing.*;

import javax.swing.table.*;

public class MouseOverHintManager implements MouseListener {

  private Map hintMap;

  private JLabel hintLabel;

  public MouseOverHintManager( JLabel hintLabel ) {

    hintMap = new WeakHashMap();

    this.hintLabel = hintLabel;

  }

  public void addHintFor( Component comp, String hintText ) {

    hintMap.put( comp, hintText );

  }

  public void enableHints( Component comp ) {

    comp.addMouseListener( this );

    if ( comp instanceof Container ) {

      Component[] components = ((Container)comp).getComponents();

      for ( int i=0; i<components.length; i++ )

       enableHints( components[i] );

    }

    if ( comp instanceof MenuElement ) {

      MenuElement[] elements = ((MenuElement)comp).getSubElements();

      for ( int i=0; i<elements.length; i++ )

       enableHints( elements[i].getComponent() );

    }

  }

  private String getHintFor( Component comp ) {

    String hint = (String)hintMap.get(comp);

    if ( hint == null ) {

      if ( comp instanceof JLabel )

       hint = (String)hintMap.get(((JLabel)comp).getLabelFor());

      else if ( comp instanceof JTableHeader )

       hint = (String)hintMap.get(((JTableHeader)comp).getTable());

    }

    return hint;

  }

  public void mouseEntered( MouseEvent e ) {

    Component comp = (Component)e.getSource();

    String hint;

    do {

      hint = getHintFor(comp);

      comp = comp.getParent();

    } while ( (hint == null) && (comp != null) );

    if ( hint != null )

      hintLabel.setText( hint );

  }

  public void mouseExited( MouseEvent e ) {

    hintLabel.setText( " " );

  }

  public void mouseClicked( MouseEvent e ) {}

  public void mousePressed( MouseEvent e ) {}

  public void mouseReleased( MouseEvent e ) {}

}