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Diffstat (limited to 'jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CachingTransformationWritablePropertyValueModel.java')
-rw-r--r-- | jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CachingTransformationWritablePropertyValueModel.java | 107 |
1 files changed, 0 insertions, 107 deletions
diff --git a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CachingTransformationWritablePropertyValueModel.java b/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CachingTransformationWritablePropertyValueModel.java deleted file mode 100644 index f9c7f11318..0000000000 --- a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/model/value/CachingTransformationWritablePropertyValueModel.java +++ /dev/null @@ -1,107 +0,0 @@ -/******************************************************************************* - * Copyright (c) 2008, 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.utility.internal.model.value; - -import org.eclipse.jpt.utility.internal.BidiTransformer; -import org.eclipse.jpt.utility.model.value.WritablePropertyValueModel; - -/** - * A <code>CachingTransformationWritablePropertyValueModel<code> augments the - * behavior of a {@link TransformationWritablePropertyValueModel} by caching - * the transformed value. - * The transformed value is calculated and cached during initialization and every - * time the wrapped value changes. This can be useful when the old value - * passed in to {@link #valueChanged(org.eclipse.jpt.utility.model.event.PropertyChangeEvent)} - * can no longer be "transformed" because its state is no longer valid. - * This caching can also improve time performance in some situations. - */ -public class CachingTransformationWritablePropertyValueModel<T1, T2> - extends TransformationWritablePropertyValueModel<T1, T2> -{ - /** - * Cache the transformed value so that during property change event notification - * we do not have to transform the old value. The old value could no longer be valid in - * the model; as a result, transforming it would not be valid. - */ - protected T2 cachedValue; - - - // ********** constructors/initialization ********** - - /** - * Construct a writable property value model with the specified nested - * writable property value model and the default bidi transformer. - * Use this constructor if you want to override - * {@link #transform_(Object)} and {@link reverseTransform_(Object)} - * (or {@link #transform(Object)} and {@link #reverseTransform(Object)}) - * methods instead of building a {@link BidiTransformer}. - */ - public CachingTransformationWritablePropertyValueModel(WritablePropertyValueModel<T1> valueHolder) { - super(valueHolder); - } - - /** - * Construct a writable property value model with the specified nested - * writable property value model and bidi transformer. - */ - public CachingTransformationWritablePropertyValueModel(WritablePropertyValueModel<T1> valueHolder, BidiTransformer<T1, T2> transformer) { - super(valueHolder, transformer); - } - - - // ********** behavior ********** - - /** - * We have listeners, transform the nested value and cache the result. - */ - @Override - protected void engageModel() { - super.engageModel(); - this.cachedValue = this.transform(this.valueHolder.getValue()); - } - - /** - * We have no more listeners, clear the cached value. - */ - @Override - protected void disengageModel() { - this.cachedValue = null; - super.disengageModel(); - } - - /** - * No need to transform the nested value, simply return the cached value, - * which is already transformed. - */ - @Override - public T2 getValue() { - return this.cachedValue; - } - - /** - * Transform the specified new value, caching it before returning it. - * A bit of a side-effect, but it seems reasonable. - */ - @Override - protected T2 transformNew(T1 value) { - this.cachedValue = super.transformNew(value); - return this.cachedValue; - } - - /** - * No need to transform the old value, simply return the cached value, - * which is already transformed. - */ - @Override - protected T2 transformOld(T1 value) { - return this.cachedValue; - } - -} |