org.eclipse.persistence.internal.queries.ReportItem Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of eclipselink Show documentation
Show all versions of eclipselink Show documentation
EclipseLink build based upon Git transaction f2b9fc5
/*
* Copyright (c) 1998, 2021 Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2019 IBM Corporation. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// Oracle - initial API and implementation from Oracle TopLink
package org.eclipse.persistence.internal.queries;
import org.eclipse.persistence.exceptions.*;
import org.eclipse.persistence.expressions.*;
import org.eclipse.persistence.mappings.*;
import org.eclipse.persistence.descriptors.ClassDescriptor;
import org.eclipse.persistence.queries.*;
import org.eclipse.persistence.internal.expressions.FunctionExpression;
import org.eclipse.persistence.internal.expressions.QueryKeyExpression;
/**
* Purpose: represents an item requested (i.e. field for SELECT)
*
* @author Doug Clarke
* @since 2.0
*/
public class ReportItem implements Cloneable, java.io.Serializable {
/** Expression (partial) describing the attribute wanted */
protected Expression attributeExpression;
/** Name given for item, can be used to retrieve value from result. Useful if same field retrieved multiple times */
protected String name;
/** Mapping which relates field to attribute, used to convert value and determine reference descriptor */
protected DatabaseMapping mapping;
/** Descriptor for object result that is not based on an expression */
protected ClassDescriptor descriptor;
/** Result type for this report item. */
protected Class resultType;
/** Stores the Join information for this item */
protected JoinedAttributeManager joinedAttributeManager;
/** Stores the row index for this item, given multiple results and joins */
protected int resultIndex;
public ReportItem() {
super();
}
public ReportItem(String name, Expression attributeExpression) {
this();
this.name = name;
this.attributeExpression = attributeExpression;
}
@Override
public Object clone(){
try{
return super.clone();
} catch (CloneNotSupportedException e) {
return null;
}
}
public Expression getAttributeExpression() {
return attributeExpression;
}
public void setAttributeExpression(Expression attributeExpression) {
this.attributeExpression = attributeExpression;
}
public ClassDescriptor getDescriptor(){
return this.descriptor;
}
/**
* INTERNAL:
* Set the list of expressions that represent elements that are joined because of their
* mapping for this query.
*/
public JoinedAttributeManager getJoinedAttributeManager() {
if (this.joinedAttributeManager == null) {
this.joinedAttributeManager = new JoinedAttributeManager();
}
return this.joinedAttributeManager;
}
public JoinedAttributeManager getJoinedAttributeManagerInternal(){
return joinedAttributeManager;
}
/**
* INTERNAL:
* Return if any attributes are joined.
* To avoid the initialization of the JoinedAttributeManager this should be first checked before accessing.
*/
public boolean hasJoining() {
return this.joinedAttributeManager != null;
}
public DatabaseMapping getMapping() {
return mapping;
}
public String getName() {
return name;
}
public int getResultIndex() {
return resultIndex;
}
public Class getResultType() {
return resultType;
}
/**
* INTERNAL:
* Looks up mapping for attribute during preExecute of ReportQuery
*/
public void initialize(ReportQuery query) throws QueryException {
if (this.mapping == null) {
if (this.attributeExpression != null) {
DatabaseMapping mapping = this.attributeExpression.getLeafMapping(query, query.getDescriptor(), query.getSession());
if (mapping == null) {
//TODO: This feels like it should be set earlier during ReportItemBuild.visit. Should investigate.
if (this.attributeExpression.isExpressionBuilder()) {
Class resultClass = ((ExpressionBuilder)this.attributeExpression).getQueryClass();
if (resultClass == null) {
resultClass = query.getReferenceClass();
((ExpressionBuilder)this.attributeExpression).setQueryClass(resultClass);
}
setDescriptor(query.getSession().getDescriptor(resultClass));
if (getDescriptor().hasInheritance()) {
((ExpressionBuilder)this.attributeExpression).setShouldUseOuterJoinForMultitableInheritance(true);
}
}
} else {
if (mapping.isAbstractDirectMapping() || this.attributeExpression.isMapEntryExpression() || mapping.isAggregateObjectMapping() || mapping.isDirectCollectionMapping()){
setMapping(mapping);
//Bug4942640 Widen the check to support collection mapping too
} else if (mapping.isForeignReferenceMapping()) {
// DirectCollectionMapping doesn't have reference descriptor
if(mapping.getReferenceDescriptor() != null) {
setDescriptor(mapping.getReferenceDescriptor());
if (getDescriptor().hasInheritance()){
((QueryKeyExpression)this.attributeExpression).setShouldUseOuterJoinForMultitableInheritance(true);
}
}
} else {
throw QueryException.invalidExpressionForQueryItem(this.attributeExpression, query);
}
}
if (hasJoining()) {
this.joinedAttributeManager.setDescriptor(this.descriptor);
this.joinedAttributeManager.setBaseQuery(query);
}
if (getAttributeExpression() != null){
if (getAttributeExpression().getBuilder().wasQueryClassSetInternally()){
//rebuild if class was not set by user this ensures the query has the same base
this.attributeExpression = this.attributeExpression.rebuildOn(query.getExpressionBuilder());
}
if (hasJoining()) {
this.joinedAttributeManager.setBaseExpressionBuilder(this.attributeExpression.getBuilder());
}
} else if (hasJoining()) {
this.joinedAttributeManager.setBaseExpressionBuilder(query.getExpressionBuilder());
}
if (hasJoining()) {
this.joinedAttributeManager.prepareJoinExpressions(query.getSession());
this.joinedAttributeManager.processJoinedMappings(query.getSession());
this.joinedAttributeManager.computeJoiningMappingQueries(query.getSession());
}
}
}
}
public boolean isConstructorItem(){
return false;
}
public void setDescriptor(ClassDescriptor descriptor){
this.descriptor = descriptor;
}
public void setJoinedAttributeManager(JoinedAttributeManager joinManager){
this.joinedAttributeManager = joinManager;
}
public void setMapping(DatabaseMapping mapping) {
this.mapping = mapping;
}
public void setResultIndex(int resultIndex) {
this.resultIndex = resultIndex;
if (hasJoining()) {
getJoinedAttributeManager().setParentResultIndex(resultIndex);
}
}
public void setResultType(Class resultType) {
this.resultType = resultType;
// Set it on the attribute expression as well if it is a function.
if (getAttributeExpression()!=null && getAttributeExpression().isFunctionExpression()) {
((FunctionExpression) getAttributeExpression()).setResultType(resultType);
}
}
@Override
public String toString() {
return "ReportQueryItem(" + getName() + " -> " + getAttributeExpression() + ")";
}
}