| /******************************************************************************* |
| * Copyright (c) 2007, 2010 Oracle. All rights reserved. |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v1.0, which accompanies this distribution |
| * and is available at http://www.eclipse.org/legal/epl-v10.html. |
| * |
| * Contributors: |
| * Oracle - initial API and implementation |
| ******************************************************************************/ |
| package org.eclipse.jpt.common.utility.internal.model.value.swing; |
| |
| import javax.swing.AbstractSpinnerModel; |
| import javax.swing.SpinnerModel; |
| import javax.swing.SpinnerNumberModel; |
| import javax.swing.event.ChangeEvent; |
| import javax.swing.event.ChangeListener; |
| import org.eclipse.jpt.common.utility.internal.StringTools; |
| import org.eclipse.jpt.common.utility.internal.model.listener.awt.AWTPropertyChangeListenerWrapper; |
| import org.eclipse.jpt.common.utility.model.event.PropertyChangeEvent; |
| import org.eclipse.jpt.common.utility.model.listener.PropertyChangeListener; |
| import org.eclipse.jpt.common.utility.model.value.PropertyValueModel; |
| import org.eclipse.jpt.common.utility.model.value.WritablePropertyValueModel; |
| |
| /** |
| * This javax.swing.SpinnerModel can be used to keep a ChangeListener |
| * (e.g. a JSpinner) in synch with a PropertyValueModel that holds a value. |
| * |
| * Note: it is likely you want to use one of the following classes instead of |
| * this one: |
| * DateSpinnerModelAdapter |
| * NumberSpinnerModelAdapter |
| * ListSpinnerModelAdapter |
| * |
| * NB: This model should only be used for values that have a fairly |
| * inexpensive #equals() implementation. |
| * @see #synchronizeDelegate(Object) |
| */ |
| public class SpinnerModelAdapter |
| extends AbstractSpinnerModel |
| { |
| /** The delegate spinner model whose behavior we "enhance". */ |
| protected final SpinnerModel delegate; |
| |
| /** A listener that allows us to forward any changes made to the delegate spinner model. */ |
| protected final ChangeListener delegateListener; |
| |
| /** A value model on the underlying value. */ |
| protected final WritablePropertyValueModel<Object> valueHolder; |
| |
| /** A listener that allows us to synchronize with changes made to the underlying value. */ |
| protected final PropertyChangeListener valueListener; |
| |
| |
| // ********** constructors ********** |
| |
| /** |
| * Constructor - the value holder and delegate are required. |
| */ |
| public SpinnerModelAdapter(WritablePropertyValueModel<Object> valueHolder, SpinnerModel delegate) { |
| super(); |
| if (valueHolder == null || delegate == null) { |
| throw new NullPointerException(); |
| } |
| this.valueHolder = valueHolder; |
| this.delegate = delegate; |
| // postpone listening to the underlying value |
| // until we have listeners ourselves... |
| this.valueListener = this.buildValueListener(); |
| this.delegateListener = this.buildDelegateListener(); |
| } |
| |
| /** |
| * Constructor - the value holder is required. |
| * This will wrap a simple number spinner model. |
| */ |
| public SpinnerModelAdapter(WritablePropertyValueModel<Object> valueHolder) { |
| this(valueHolder, new SpinnerNumberModel()); |
| } |
| |
| |
| // ********** initialization ********** |
| |
| protected PropertyChangeListener buildValueListener() { |
| return new AWTPropertyChangeListenerWrapper(this.buildValueListener_()); |
| } |
| |
| protected PropertyChangeListener buildValueListener_() { |
| return new PropertyChangeListener() { |
| public void propertyChanged(PropertyChangeEvent event) { |
| SpinnerModelAdapter.this.valueChanged(event); |
| } |
| @Override |
| public String toString() { |
| return "value listener"; //$NON-NLS-1$ |
| } |
| }; |
| } |
| |
| /** |
| * expand access a bit for inner class |
| */ |
| @Override |
| protected void fireStateChanged() { |
| super.fireStateChanged(); |
| } |
| |
| protected ChangeListener buildDelegateListener() { |
| return new ChangeListener() { |
| public void stateChanged(ChangeEvent event) { |
| // forward the event, with this as the source |
| SpinnerModelAdapter.this.fireStateChanged(); |
| } |
| @Override |
| public String toString() { |
| return "delegate listener"; //$NON-NLS-1$ |
| } |
| }; |
| } |
| |
| |
| // ********** SpinnerModel implementation ********** |
| |
| public Object getValue() { |
| return this.delegate.getValue(); |
| } |
| |
| /** |
| * Extend to update the underlying value directly. |
| * The resulting event will be ignored: @see #synchronizeDelegate(Object). |
| */ |
| public void setValue(Object value) { |
| this.delegate.setValue(value); |
| this.valueHolder.setValue(value); |
| } |
| |
| public Object getNextValue() { |
| return this.delegate.getNextValue(); |
| } |
| |
| public Object getPreviousValue() { |
| return this.delegate.getPreviousValue(); |
| } |
| |
| /** |
| * Extend to start listening to the underlying value if necessary. |
| */ |
| @Override |
| public void addChangeListener(ChangeListener listener) { |
| if (this.listenerList.getListenerCount(ChangeListener.class) == 0) { |
| this.delegate.addChangeListener(this.delegateListener); |
| this.engageValueHolder(); |
| } |
| super.addChangeListener(listener); |
| } |
| |
| /** |
| * Extend to stop listening to the underlying value if appropriate. |
| */ |
| @Override |
| public void removeChangeListener(ChangeListener listener) { |
| super.removeChangeListener(listener); |
| if (this.listenerList.getListenerCount(ChangeListener.class) == 0) { |
| this.disengageValueHolder(); |
| this.delegate.removeChangeListener(this.delegateListener); |
| } |
| } |
| |
| |
| // ********** behavior ********** |
| |
| /** |
| * A third party has modified the underlying value. |
| * Synchronize the delegate model accordingly. |
| */ |
| protected void valueChanged(PropertyChangeEvent event) { |
| this.synchronizeDelegate(event.getNewValue()); |
| } |
| |
| /** |
| * Set the delegate's value if it has changed. |
| */ |
| protected void synchronizeDelegate(Object value) { |
| // check to see whether the delegate has already been synchronized |
| // (via #setValue()) |
| if ( ! this.delegate.getValue().equals(value)) { |
| this.delegate.setValue(value); |
| } |
| } |
| |
| protected void engageValueHolder() { |
| this.valueHolder.addPropertyChangeListener(PropertyValueModel.VALUE, this.valueListener); |
| this.synchronizeDelegate(this.valueHolder.getValue()); |
| } |
| |
| protected void disengageValueHolder() { |
| this.valueHolder.removePropertyChangeListener(PropertyValueModel.VALUE, this.valueListener); |
| } |
| |
| |
| // ********** standard methods ********** |
| |
| @Override |
| public String toString() { |
| return StringTools.buildToStringFor(this, this.valueHolder); |
| } |
| |
| } |