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Diffstat (limited to 'common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/CachingTransformationPropertyValueModel.java')
-rw-r--r--common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/CachingTransformationPropertyValueModel.java112
1 files changed, 0 insertions, 112 deletions
diff --git a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/CachingTransformationPropertyValueModel.java b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/CachingTransformationPropertyValueModel.java
deleted file mode 100644
index c62e6853bf..0000000000
--- a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/model/value/CachingTransformationPropertyValueModel.java
+++ /dev/null
@@ -1,112 +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.common.utility.internal.model.value;
-
-import org.eclipse.jpt.common.utility.internal.Transformer;
-import org.eclipse.jpt.common.utility.model.value.PropertyValueModel;
-
-/**
- * A <code>CachingTransformationPropertyValueModel</code> wraps another
- * {@link PropertyValueModel} and uses a {@link Transformer}
- * to transform the wrapped value before it is returned by {@link #getValue()}.
- * 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.common.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- * can no longer be "transformed" because its state is no longer valid.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.
- * <p>
- * As an alternative to building a {@link Transformer},
- * a subclass of <code>CachingTransformationPropertyValueModel</code> can
- * either override {@link #transform_(Object)} or,
- * if something other than null should be returned when the wrapped value
- * is null, override {@link #transform(Object)}.
- */
-public class CachingTransformationPropertyValueModel<T1, T2>
- extends TransformationPropertyValueModel<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 property value model with the specified nested
- * property value model and the default transformer.
- * Use this constructor if you want to override
- * {@link #transform_(Object)} or {@link #transform(Object)}
- * instead of building a {@link Transformer}.
- */
- public CachingTransformationPropertyValueModel(PropertyValueModel<? extends T1> valueHolder) {
- super(valueHolder);
- }
-
- /**
- * Construct an property value model with the specified nested
- * property value model and transformer.
- */
- public CachingTransformationPropertyValueModel(PropertyValueModel<? extends T1> valueHolder, Transformer<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;
- }
-
-}

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