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Diffstat (limited to 'jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/PropertyAspectAdapter.java')
| -rw-r--r-- | jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/PropertyAspectAdapter.java | 256 |
1 files changed, 0 insertions, 256 deletions
diff --git a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/PropertyAspectAdapter.java b/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/PropertyAspectAdapter.java deleted file mode 100644 index 1b4d206abb..0000000000 --- a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/PropertyAspectAdapter.java +++ /dev/null @@ -1,256 +0,0 @@ -/******************************************************************************* - * Copyright (c) 2007 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.utility.internal.model.value; - -import java.util.Arrays; -import java.util.Collection; - -import org.eclipse.jpt.utility.internal.model.Model; -import org.eclipse.jpt.utility.internal.model.event.PropertyChangeEvent; -import org.eclipse.jpt.utility.internal.model.listener.ChangeListener; -import org.eclipse.jpt.utility.internal.model.listener.PropertyChangeListener; - -/** - * This AspectAdapter provides basic PropertyChange support. - * This allows us to convert a set of one or more properties into - * a single property, VALUE. - * - * The typical subclass will override the following methods: - * #getValueFromSubject() - * at the very minimum, override this method to return the value of the - * subject's property (or "virtual" property); it does not need to be - * overridden if #buildValue() is overridden and its behavior changed - * #setValueOnSubject(Object) - * override this method if the client code needs to *set* the value of - * the subject's property; oftentimes, though, the client code (e.g. UI) - * will need only to *get* the value; it does not need to be - * overridden if #setValue(Object) is overridden and its behavior changed - * #buildValue() - * override this method only if returning a null value when the subject is null - * is unacceptable - * #setValue(Object) - * override this method only if something must be done when the subject - * is null (e.g. throw an exception) - */ -public abstract class PropertyAspectAdapter - extends AspectAdapter - implements PropertyValueModel -{ - /** - * Cache the current value of the aspect so we - * can pass an "old value" when we fire a property change event. - * We need this because the value may be calculated and may - * not be in the property change event fired by the subject, - * especially when dealing with multiple aspects. - */ - protected Object value; - - /** The name of the subject's properties that we use for the value. */ - protected final String[] propertyNames; - private static final String[] EMPTY_PROPERTY_NAMES = new String[0]; - - /** A listener that listens to the appropriate properties of the subject. */ - protected final PropertyChangeListener propertyChangeListener; - - - // ********** constructors ********** - - /** - * Construct a PropertyAspectAdapter for the specified subject - * and property. - */ - protected PropertyAspectAdapter(String propertyName, Model subject) { - this(new String[] {propertyName}, subject); - } - - /** - * Construct a PropertyAspectAdapter for the specified subject - * and properties. - */ - protected PropertyAspectAdapter(String[] propertyNames, Model subject) { - this(new ReadOnlyPropertyValueModel(subject), propertyNames); - } - - /** - * Construct a PropertyAspectAdapter for the specified subject holder - * and properties. - */ - protected PropertyAspectAdapter(ValueModel subjectHolder, String... propertyNames) { - super(subjectHolder); - this.propertyNames = propertyNames; - this.propertyChangeListener = this.buildPropertyChangeListener(); - // our value is null when we are not listening to the subject - this.value = null; - } - - /** - * Construct a PropertyAspectAdapter for the specified subject holder - * and properties. - */ - protected PropertyAspectAdapter(ValueModel subjectHolder, Collection<String> propertyNames) { - this(subjectHolder, propertyNames.toArray(new String[propertyNames.size()])); - } - - /** - * Construct a PropertyAspectAdapter for an "unchanging" property in - * the specified subject. This is useful for a property aspect that does not - * change for a particular subject; but the subject will change, resulting in - * a new property. - */ - protected PropertyAspectAdapter(ValueModel subjectHolder) { - this(subjectHolder, EMPTY_PROPERTY_NAMES); - } - - - // ********** initialization ********** - - /** - * The subject's property has changed, notify the listeners. - */ - protected PropertyChangeListener buildPropertyChangeListener() { - // transform the subject's property change events into VALUE property change events - return new PropertyChangeListener() { - public void propertyChanged(PropertyChangeEvent e) { - PropertyAspectAdapter.this.propertyChanged(); - } - @Override - public String toString() { - return "property change listener: " + Arrays.asList(PropertyAspectAdapter.this.propertyNames); - } - }; - } - - - // ********** ValueModel implementation ********** - - /** - * Return the value of the subject's property. - */ - @Override - public final Object value() { - return this.value; - } - - - // ********** PropertyValueModel implementation ********** - - /** - * Set the value of the subject's property. - */ - public void setValue(Object value) { - if (this.subject != null) { - this.setValueOnSubject(value); - } - } - - /** - * Set the value of the subject's property. - * At this point we can be sure that the subject is not null. - * @see #setValue(Object) - */ - protected void setValueOnSubject(Object value) { - throw new UnsupportedOperationException(); - } - - - // ********** AspectAdapter implementation ********** - - @Override - protected Class<? extends ChangeListener> listenerClass() { - return PropertyChangeListener.class; - } - - @Override - protected String listenerAspectName() { - return VALUE; - } - - @Override - protected boolean hasListeners() { - return this.hasAnyPropertyChangeListeners(VALUE); - } - - @Override - protected void fireAspectChange(Object oldValue, Object newValue) { - this.firePropertyChanged(VALUE, oldValue, newValue); - } - - @Override - protected void engageSubject() { - super.engageSubject(); - // synch our value *after* we start listening to the subject, - // since its value might change when a listener is added - this.value = this.buildValue(); - } - - @Override - protected void engageNonNullSubject() { - for (int i = this.propertyNames.length; i-- > 0; ) { - ((Model) this.subject).addPropertyChangeListener(this.propertyNames[i], this.propertyChangeListener); - } - } - - @Override - protected void disengageSubject() { - super.disengageSubject(); - // clear out our value when we are not listening to the subject - this.value = null; - } - - @Override - protected void disengageNonNullSubject() { - for (int i = this.propertyNames.length; i-- > 0; ) { - ((Model) this.subject).removePropertyChangeListener(this.propertyNames[i], this.propertyChangeListener); - } - } - - - // ********** AbstractModel implementation ********** - - @Override - public void toString(StringBuilder sb) { - for (int i = 0; i < this.propertyNames.length; i++) { - if (i != 0) { - sb.append(", "); - } - sb.append(this.propertyNames[i]); - } - } - - - // ********** behavior ********** - - /** - * Return the aspect's value. - * At this point the subject may be null. - */ - protected Object buildValue() { - if (this.subject == null) { - return null; - } - return this.getValueFromSubject(); - } - - /** - * Return the value of the subject's property. - * At this point we can be sure that the subject is not null. - * @see #value() - */ - protected Object getValueFromSubject() { - throw new UnsupportedOperationException(); - } - - protected void propertyChanged() { - Object old = this.value; - this.value = this.buildValue(); - this.fireAspectChange(old, this.value); - } - -} |