/******************************************************************************* | |
* Copyright (c) 1998, 2013 Oracle and/or its affiliates. All rights reserved. | |
* This program and the accompanying materials are made available under the | |
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0 | |
* which accompanies this distribution. | |
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html | |
* and the Eclipse Distribution License is available at | |
* http://www.eclipse.org/org/documents/edl-v10.php. | |
* | |
* Contributors: | |
* Oracle - initial API and implementation from Oracle TopLink | |
******************************************************************************/ | |
package org.eclipse.persistence.internal.expressions; | |
import java.util.*; | |
import org.eclipse.persistence.expressions.*; | |
/** | |
* Generic class for an expression with a base. | |
* The base is the expression that this one is derived from. | |
*/ | |
public abstract class BaseExpression extends Expression { | |
/** The base expression is what this was derived from. */ | |
protected Expression baseExpression; | |
/** PERF: Used to cache the builder. */ | |
protected ExpressionBuilder builder; | |
public BaseExpression() { | |
super(); | |
} | |
public BaseExpression(Expression baseExpression) { | |
super(); | |
this.baseExpression = baseExpression; | |
} | |
/** | |
* The base expression is what the parameter was derived from. | |
*/ | |
public Expression getBaseExpression() { | |
return baseExpression; | |
} | |
/** | |
* Return the expression builder which is the ultimate base of this expression, or | |
* null if there isn't one (shouldn't happen if we start from a root). | |
*/ | |
public ExpressionBuilder getBuilder() { | |
if ((this.builder == null) && (baseExpression != null)) { | |
this.builder = baseExpression.getBuilder(); | |
} | |
return this.builder; | |
} | |
/** | |
* INTERNAL: | |
* Used for cloning. | |
*/ | |
protected void postCopyIn(Map alreadyDone) { | |
super.postCopyIn(alreadyDone); | |
if (this.baseExpression != null) { | |
setBaseExpression(this.baseExpression.copiedVersionFrom(alreadyDone)); | |
} | |
} | |
/** | |
* INTERNAL: | |
* Search the tree for any expressions (like SubSelectExpressions) that have been | |
* built using a builder that is not attached to the query. This happens in case of an Exists | |
* call using a new ExpressionBuilder(). This builder needs to be replaced with one from the query. | |
*/ | |
public void resetPlaceHolderBuilder(ExpressionBuilder queryBuilder){ | |
if (this.baseExpression != null){ | |
this.baseExpression.resetPlaceHolderBuilder(queryBuilder); | |
} | |
} | |
/** | |
* The base expression is what the parameter was derived from. | |
* This is used for nested parameters. | |
*/ | |
public void setBaseExpression(Expression baseExpression) { | |
this.baseExpression = baseExpression; | |
this.builder = null; | |
} | |
/** | |
* INTERNAL: | |
* Clear the builder when cloning. | |
*/ | |
public Expression shallowClone() { | |
BaseExpression clone = (BaseExpression)super.shallowClone(); | |
clone.builder = null; | |
return clone; | |
} | |
} |