oracle.toplink.essentials.internal.parsing.EqualsNode Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
* [name of copyright owner]
*/
// Copyright (c) 1998, 2007, Oracle. All rights reserved.
package oracle.toplink.essentials.internal.parsing;
import oracle.toplink.essentials.expressions.*;
import oracle.toplink.essentials.exceptions.EJBQLException;
/**
* INTERNAL
* Purpose: Represent an '=' in EJBQL
*
Responsibilities:
* - Generate the correct expression for an '=' in EJBQL
*
* @author Jon Driscoll and Joel Lucuik
* @since TopLink 4.0
*/
public class EqualsNode extends BinaryOperatorNode {
/**
* EqualsNode constructor comment.
*/
public EqualsNode() {
super();
}
/**
* INTERNAL
* Validate node and calculates its type.
*/
public void validate(ParseTreeContext context) {
super.validate(context);
TypeHelper typeHelper = context.getTypeHelper();
Object leftType = left.getType();
Object rightType = right.getType();
if (typeHelper.isEnumType(leftType) && !typeHelper.isEnumType(rightType)) {
throw EJBQLException.invalidEnumEqualExpression(
context.getQueryInfo(), getLine(), getColumn(),
typeHelper.getTypeName(leftType), typeHelper.getTypeName(rightType));
} else if (typeHelper.isEnumType(rightType) && !typeHelper.isEnumType(leftType)) {
throw EJBQLException.invalidEnumEqualExpression(
context.getQueryInfo(), getLine(), getColumn(),
typeHelper.getTypeName(rightType), typeHelper.getTypeName(leftType));
}
setType(typeHelper.getBooleanType());
}
/**
* Resolve the expression. The steps are:
* 1. Set the expressionBuilder for the left and right nodes
* 2. Generate the expression for the left node
* 3. Add the .equals to the where clause returned from step 2
* 4. Generate the expression for the right side and use it as the parameter for the .equals()
* 5. Return the completed where clause to the caller
*/
public Expression generateExpression(GenerationContext context) {
Expression whereClause = getLeft().generateExpression(context);
whereClause = whereClause.equal(getRight().generateExpression(context));
return whereClause;
}
/**
* INTERNAL
* Get the string representation of this node.
*/
public String getAsString() {
return left.getAsString() + " = " + right.getAsString();
}
}