A simple AbstractBean

Just in case, here is a simple example of an AbstractBean class that can be used as a base class for JavaBeans if you want to use the Eclipse bouded setter plugin.

public abstract class AbstractBean {
    /**
     * Create a new change support
     */
    protected PropertyChangeSupport change = new EDTSafePropertyChangeSupport(this);

    /**
     * @param listener
     * @see java.beans.PropertyChangeSupport#addPropertyChangeListener(java.beans.PropertyChangeListener)
     */
    public void addPropertyChangeListener(PropertyChangeListener listener) {
        change.addPropertyChangeListener(listener);
    }

    /**
     * @param propertyName
     * @param listener
     * @see java.beans.PropertyChangeSupport#addPropertyChangeListener(java.lang.String, java.beans.PropertyChangeListener)
     */
    public void addPropertyChangeListener(String propertyName,
            PropertyChangeListener listener) {
        change.addPropertyChangeListener(propertyName, listener);
    }

    /**
     * @param propertyName
     * @param oldValue
     * @param newValue
     * @see java.beans.PropertyChangeSupport#firePropertyChange(java.lang.String, java.lang.Object, java.lang.Object)
     */
    public void firePropertyChange(String propertyName, Object oldValue,
            Object newValue) {
        change.firePropertyChange(propertyName, oldValue, newValue);
    }

    /**
     * @return
     * @see java.beans.PropertyChangeSupport#getPropertyChangeListeners()
     */
    public PropertyChangeListener[] getPropertyChangeListeners() {
        return change.getPropertyChangeListeners();
    }

    /**
     * @param propertyName
     * @return
     * @see java.beans.PropertyChangeSupport#getPropertyChangeListeners(java.lang.String)
     */
    public PropertyChangeListener[] getPropertyChangeListeners(
            String propertyName) {
        return change.getPropertyChangeListeners(propertyName);
    }

    /**
     * @param propertyName
     * @return
     * @see java.beans.PropertyChangeSupport#hasListeners(java.lang.String)
     */
    public boolean hasListeners(String propertyName) {
        return change.hasListeners(propertyName);
    }

    /**
     * @param listener
     * @see java.beans.PropertyChangeSupport#removePropertyChangeListener(java.beans.PropertyChangeListener)
     */
    public void removePropertyChangeListener(PropertyChangeListener listener) {
        change.removePropertyChangeListener(listener);
    }

    /**
     * @param propertyName
     * @param listener
     * @see java.beans.PropertyChangeSupport#removePropertyChangeListener(java.lang.String, java.beans.PropertyChangeListener)
     */
    public void removePropertyChangeListener(String propertyName,
            PropertyChangeListener listener) {
        change.removePropertyChangeListener(propertyName, listener);
    }

    /**
     * Simply ensures that events are delivered through the event dispatching thread
     *
     */
    class EDTSafePropertyChangeSupport extends PropertyChangeSupport{
        public EDTSafePropertyChangeSupport(Object sourceBean) {
            super(sourceBean);
        }
        @Override
        public void firePropertyChange(final PropertyChangeEvent evt) {
            if(SwingUtilities.isEventDispatchThread()){
                super.firePropertyChange(evt);
            }else{
                SwingUtilities.invokeLater(new Runnable() {
                    public void run() {
                        firePropertyChange(evt);
                    }
                });
            }
        }
    }
}

This implementation restricts itself to the firePropertyChange(String,Object,Object) method. It also provide a custom extension of PropertyChangeSupport that ensures that events are fired in the EventDispatchingThread.

Tags: AbstractBean, bound properties, JavaBeans

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