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Diffstat (limited to 'common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/ValueAspectAdapter.java')
-rw-r--r-- | common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/ValueAspectAdapter.java | 201 |
1 files changed, 0 insertions, 201 deletions
diff --git a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/ValueAspectAdapter.java b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/ValueAspectAdapter.java deleted file mode 100644 index 5876d5e444..0000000000 --- a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/ValueAspectAdapter.java +++ /dev/null @@ -1,201 +0,0 @@ -/******************************************************************************* - * Copyright (c) 2007, 2009 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; - -import org.eclipse.jpt.common.utility.internal.model.ChangeSupport; -import org.eclipse.jpt.common.utility.model.event.PropertyChangeEvent; -import org.eclipse.jpt.common.utility.model.listener.StateChangeListener; -import org.eclipse.jpt.common.utility.model.value.WritablePropertyValueModel; - -/** - * Abstract class that provides support for wrapping a {@link WritablePropertyValueModel} - * and listening for changes to <em>aspects</em> of the <em>value</em> contained - * by the {@link WritablePropertyValueModel}. Changes to the {@link WritablePropertyValueModel}'s - * value are also monitored. - * <p> - * This is useful if you have a value that may change, but whose aspects can also - * change in a fashion that might be of interest to the client. - * <p> - * <strong>NB:</strong> Clients will need to listen for two different change notifications: - * a property change event will be be fired when the <em>value</em> changes; - * a state change event will be fired when an <em>aspect</em> of the value changes. - * <p> - * Subclasses need to override two methods:<ul> - * <li>{@link #engageValue_()}<p> - * begin listening to the appropriate aspect of the value and call - * {@link #valueAspectChanged()} whenever the aspect changes - * (this will fire a state change event) - * <li>{@link #disengageValue_()}<p> - * stop listening to the appropriate aspect of the value - * </ul> - */ -public abstract class ValueAspectAdapter<V> - extends PropertyValueModelWrapper<V> - implements WritablePropertyValueModel<V> -{ - /** Cache the value so we can disengage. Null until we have a listener*/ - protected V value; - - - // ********** constructors/initialization ********** - - /** - * Constructor - the value holder is required. - */ - protected ValueAspectAdapter(WritablePropertyValueModel<V> valueHolder) { - super(valueHolder); - this.value = null; - } - - /** - * Override to allow both property and state change listeners. - */ - @Override - protected ChangeSupport buildChangeSupport() { - return new ChangeSupport(this); - } - - - // ********** PropertyValueModel implementation ********** - - public V getValue() { - return this.value; - } - - - // ********** WritablePropertyValueModel implementation ********** - - public void setValue(V value) { - this.getValueHolder().setValue(value); - } - - - // ********** PropertyValueModelWrapper implementation ********** - - @Override - protected void valueChanged(PropertyChangeEvent event) { - this.disengageValue(); - this.engageValue(); - this.firePropertyChanged(event.clone(this)); - } - - - // ********** extend change support ********** - - /** - * Extend to start listening to the underlying model if necessary. - */ - @Override - public synchronized void addStateChangeListener(StateChangeListener listener) { - if (this.hasNoListeners()) { - this.engageModel(); - } - super.addStateChangeListener(listener); - } - - /** - * Extend to stop listening to the underlying model if necessary. - */ - @Override - public synchronized void removeStateChangeListener(StateChangeListener listener) { - super.removeStateChangeListener(listener); - if (this.hasNoListeners()) { - this.disengageModel(); - } - } - - - // ********** AbstractPropertyValueModel overrides ********** - - /** - * Extend to check for state change listeners. - */ - @Override - protected boolean hasListeners() { - return this.hasAnyStateChangeListeners() || super.hasListeners(); - } - - - // ********** PropertyValueModelWrapper overrides ********** - - /** - * Extend to engage an aspect of the value model's value. - */ - @Override - protected void engageModel() { - super.engageModel(); - this.engageValue(); - } - - /** - * Extend to disengage an aspect of the value model's value. - */ - @Override - protected void disengageModel() { - this.disengageValue(); - super.disengageModel(); - } - - - // ********** behavior ********** - - /** - * Start listening to an aspect of the current value. - */ - protected void engageValue() { - this.value = this.valueHolder.getValue(); - if (this.value != null) { - this.engageValue_(); - } - } - - /** - * Start listening to some aspect of the current value. - * At this point we can be sure the value is not null. - */ - protected abstract void engageValue_(); - - /** - * Stop listening to an aspect of the current value. - */ - protected void disengageValue() { - if (this.value != null) { - this.disengageValue_(); - this.value = null; - } - } - - /** - * Stop listening to an aspect of the current value. - * At this point we can be sure the value is not null. - */ - protected abstract void disengageValue_(); - - /** - * Subclasses should call this method whenever the value's aspect changes. - */ - protected void valueAspectChanged() { - this.fireStateChanged(); - } - - /** - * Our constructor accepts only a {@link WritablePropertyValueModel}{@code<V>}. - */ - @SuppressWarnings("unchecked") - protected WritablePropertyValueModel<V> getValueHolder() { - return (WritablePropertyValueModel<V>) this.valueHolder; - } - - @Override - public void toString(StringBuilder sb) { - sb.append(this.getValue()); - } - -} |