org.eclipse.persistence.internal.jpa.parsing.OrNode Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of eclipselink Show documentation
EclipseLink build based upon Git transaction f2b9fc5
There is a newer version: 5.0.0-B03
/*
 * Copyright (c) 1998, 2018 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:
//     Oracle - initial API and implementation from Oracle TopLink
package org.eclipse.persistence.internal.jpa.parsing;

import java.util.*;

import org.eclipse.persistence.expressions.*;

/**
 * INTERNAL
 * Purpose: Represent an OR
 * 
Responsibilities:

 *  Generate the correct expression for an OR
 * 
 *    @author Jon Driscoll and Joel Lucuik
 *    @since TopLink 4.0
 */
public class OrNode extends LogicalOperatorNode {

    private Set leftOuterScopeVariables = null;
    private Set rightOuterScopeVariables = null;

    /**
     * Return a new OrNode.
     */
    public OrNode() {
        super();
    }

    /**
     * INTERNAL
     * Validate node and calculate its type.
     */
    public void validate(ParseTreeContext context) {
        Set saved = context.getOuterScopeVariables();
        if (left != null) {
            context.resetOuterScopeVariables();
            left.validate(context);
            leftOuterScopeVariables = context.getOuterScopeVariables();
        }
        if (right != null) {
            context.resetOuterScopeVariables();
            right.validate(context);
            rightOuterScopeVariables = context.getOuterScopeVariables();
        }
        context.resetOuterScopeVariables(saved);
        if ((left != null) && (right != null)) {
            left.validateParameter(context, right.getType());
            right.validateParameter(context, left.getType());
        }

        TypeHelper typeHelper = context.getTypeHelper();
        setType(typeHelper.getBooleanType());
    }

    /**
     * INTERNAL
     * Return a EclipseLink expression by 'OR'ing the expressions from the left and right nodes
     */
    public Expression generateExpression(GenerationContext context) {
        // Get the left expression
        Expression leftExpr = getLeft().generateExpression(context);
        leftExpr = appendOuterScopeVariableJoins(
            leftExpr, leftOuterScopeVariables, context);

        Expression rightExpr = getRight().generateExpression(context);
        rightExpr = appendOuterScopeVariableJoins(
            rightExpr, rightOuterScopeVariables, context);

        // Or it with whatever the right expression is
        return leftExpr.or(rightExpr);
    }

    /**
     * INTERNAL
     */
    private Expression appendOuterScopeVariableJoins(
        Expression expr, Set outerScopeVariables, GenerationContext context) {
        if ((outerScopeVariables == null) || outerScopeVariables.isEmpty()) {
            // no outer scope variables => nothing to be done
            return expr;
        }
        Expression joins = context.joinVariables(outerScopeVariables);
        return appendExpression(expr, joins);
    }

}