| /* |
| * Copyright (c) 2011, 2021 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 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: |
| // Gordon Yorke - Initial development |
| // |
| |
| package org.eclipse.persistence.internal.jpa.querydef; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import jakarta.persistence.criteria.Expression; |
| import jakarta.persistence.criteria.Fetch; |
| import jakarta.persistence.criteria.From; |
| import jakarta.persistence.criteria.Join; |
| import jakarta.persistence.criteria.JoinType; |
| import jakarta.persistence.criteria.Path; |
| import jakarta.persistence.criteria.Predicate; |
| import jakarta.persistence.criteria.Predicate.BooleanOperator; |
| import jakarta.persistence.metamodel.Attribute; |
| import jakarta.persistence.metamodel.Bindable; |
| import jakarta.persistence.metamodel.ManagedType; |
| import jakarta.persistence.metamodel.Metamodel; |
| |
| /** |
| * <p> |
| * <b>Purpose</b>: Contains the implementation of the Join interface of the JPA |
| * criteria API. |
| * <p> |
| * <b>Description</b>: This class represents a join of an attribute from a "From"element. |
| * |
| * @see jakarta.persistence.criteria Join |
| * |
| * @author gyorke |
| * @since EclipseLink 1.2 |
| */ |
| |
| public class JoinImpl<Z, X> extends FromImpl<Z, X> implements Join<Z, X>, Fetch<Z, X> { |
| |
| protected JoinType joinType; |
| protected Expression<Boolean> on; |
| |
| public <T> JoinImpl(Path<Z> parentPath, ManagedType managedType, Metamodel metamodel, Class<X> javaClass, org.eclipse.persistence.expressions.Expression expressionNode, Bindable<T> modelArtifact){ |
| this(parentPath, managedType, metamodel, javaClass, expressionNode, modelArtifact,JoinType.INNER); |
| } |
| |
| public <T> JoinImpl(Path<Z> parentPath, ManagedType managedType, Metamodel metamodel, Class<X> javaClass, org.eclipse.persistence.expressions.Expression expressionNode, Bindable<T> modelArtifact, JoinType joinType){ |
| super(parentPath, managedType, metamodel, javaClass, expressionNode, modelArtifact); |
| this.joinType = joinType; |
| } |
| |
| public <T> JoinImpl(Path<Z> parentPath, ManagedType managedType, Metamodel metamodel, Class<X> javaClass, org.eclipse.persistence.expressions.Expression expressionNode, Bindable<T> modelArtifact, JoinType joinType, FromImpl correlatedParent){ |
| super(parentPath, managedType, metamodel, javaClass, expressionNode, modelArtifact, correlatedParent); |
| this.joinType = joinType; |
| } |
| |
| /** |
| * Return the metamodel Attribute corresponding to the join. |
| * |
| * @return metamodel Attribute type for the join |
| */ |
| @Override |
| public Attribute<? super Z, ?> getAttribute(){ |
| //Only attributes will be stored in this field so it is ok |
| //to perform the cast. |
| return (Attribute<? super Z, ?>) this.modelArtifact; |
| } |
| |
| /** |
| * Return the parent of the join. |
| * |
| * @return join parent |
| */ |
| @Override |
| public From<?, Z> getParent(){ |
| // this cast is acceptable as by design the parent of a Join must be a from implementor |
| return (From<?, Z>)pathParent; |
| } |
| |
| /** |
| * Return the join type. |
| * |
| * @return join type |
| */ |
| @Override |
| public JoinType getJoinType(){ |
| return joinType; |
| } |
| |
| @Override |
| protected <T> Expression<T> buildExpressionForAs(Class<T> type) { |
| managedType = metamodel.managedType(type); |
| currentNode = currentNode.treat(type); |
| return (Expression<T>)this; |
| } |
| |
| @Override |
| public Predicate getOn() { |
| if (this.on == null) { |
| return null; |
| } |
| if (((ExpressionImpl)this.on).isPredicate()) return (Predicate)this.on; |
| |
| //see queryBuilder.isTrue(this.on); |
| List<Expression<?>> list = new ArrayList<>(); |
| list.add(this.on); |
| return new CompoundExpressionImpl(this.metamodel, ((InternalSelection)this.on).getCurrentNode().equal(true), list, "equals"); |
| } |
| |
| @Override |
| public JoinImpl<Z, X> on(Expression<Boolean> restriction) { |
| this.on = restriction; |
| org.eclipse.persistence.expressions.Expression onExp = restriction==null? null:((ExpressionImpl)restriction).getCurrentNode(); |
| ((PathImpl)this.pathParent).getCurrentNode().join(this.currentNode, onExp); |
| |
| return this; |
| } |
| |
| @Override |
| public JoinImpl<Z, X> on(Predicate... restrictions) { |
| org.eclipse.persistence.expressions.Expression onExp; |
| if (restrictions == null || restrictions.length == 0){ |
| this.on = null; |
| onExp = null; |
| } else { |
| //from criteriaQueryImpl.where(Predicate... restrictions) |
| Predicate a = restrictions[0]; |
| for (int i = 1; i < restrictions.length; ++i){ |
| org.eclipse.persistence.expressions.Expression currentNode = ((CompoundExpressionImpl)a).getCurrentNode().and( |
| ((CompoundExpressionImpl)restrictions[i]).getCurrentNode()); |
| ((CompoundExpressionImpl)a).setParentNode(currentNode); |
| ((CompoundExpressionImpl)restrictions[i]).setParentNode(currentNode); |
| List<Expression<?>> list = new ArrayList<>(); |
| list.add(a); |
| list.add(restrictions[i]); |
| a = new PredicateImpl(this.metamodel, currentNode, list, BooleanOperator.AND); |
| } |
| this.on = a; |
| onExp = ((ExpressionImpl)a).getCurrentNode(); |
| } |
| |
| ((PathImpl)this.pathParent).getCurrentNode().join(this.currentNode, onExp); |
| return this; |
| } |
| |
| } |