refactoring?

When you encapsulate fields.  Instead of simply generating:

class MyClass
{
    private int top;

    public int getTop()
    {
        return top;
    }

    public void setTop(int top)
    {
        this.top = top;
    }
}

it would be nice if an option for something like the following could be done:

class MyClass
{
    PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);

    private int top;

    public int getTop()
    {
        return top;
    }

    public void setTop(int top)
    {
        int old = this.top;
        this.top = top;
        propertyChangeSupport.firePropertyChange("top", old, top);
    }
}

The above code makes 'top' a bound field.  Something that also provides the
option of making a vetoable field would also be useful.

An even better way to do this would be to first check if the current class
contains a memeber which is a PropertyChangeSupport.  If not, create one,
including the add and remove listener methods.

Also, setting a static final String to be the property name would be a good idea.

class MyClass
{
    PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);

    private int top;

    public static final PROP_top = "top";

    public void addPropertyChangeListener(PropertyChangeListener l)
    {
        propertyChangeSupport.addPropertyChangeListener(l);
    }

    public void removePropertyChangeListener(PropertyChangeListener l)
    {
        propertyChangeSupport.removePropertyChangeListener(l);
    }

    public int getTop()
    {
        return top;
    }

    public void setTop(int top)
    {
        int old = this.top;
        this.top = top;
        propertyChangeSupport.firePropertyChange(PROP_top, old, top);
    }
}

*** This bug has been marked as a duplicate of bug 69498 ***