| /* |
| * Copyright (c) 2006, 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: |
| // Oracle - initial API and implementation |
| // |
| package org.eclipse.persistence.jpa.jpql.parser; |
| |
| import org.eclipse.persistence.jpa.jpql.WordParser; |
| import static org.eclipse.persistence.jpa.jpql.parser.Expression.*; |
| |
| /** |
| * This {@link IsExpressionFactory} creates a new expression when the portion of the query to parse |
| * starts with <b>IS</b>. |
| * |
| * @see EmptyCollectionComparisonExpression |
| * @see NullComparisonExpression |
| * |
| * @version 2.5 |
| * @since 2.3 |
| * @author Pascal Filion |
| */ |
| public final class IsExpressionFactory extends ExpressionFactory { |
| |
| /** |
| * The unique identifier of this {@link IsExpressionFactory}. |
| */ |
| public static final String ID = IS; |
| |
| /** |
| * Creates a new <code>IsExpressionFactory</code>. |
| */ |
| public IsExpressionFactory() { |
| super(ID, IS, |
| IS_EMPTY, |
| IS_NOT_EMPTY, |
| IS_NOT_NULL, |
| IS_NULL); |
| } |
| |
| @Override |
| protected AbstractExpression buildExpression(AbstractExpression parent, |
| WordParser wordParser, |
| String word, |
| JPQLQueryBNF queryBNF, |
| AbstractExpression expression, |
| boolean tolerant) { |
| |
| int position = wordParser.position(); |
| int index = position + 2; |
| int count = wordParser.whitespaceCount(index); |
| index += count; |
| |
| // IS NOT EMPTY or IS NOT NULL |
| if (wordParser.startsWithIdentifier(NOT, index)) { |
| index += 3; |
| count = wordParser.whitespaceCount(index); |
| index += count; |
| |
| // IS NOT EMPTY |
| if (wordParser.startsWithIdentifier(EMPTY, index)) { |
| expression = new EmptyCollectionComparisonExpression(parent, IS_NOT_EMPTY, expression); |
| } |
| // IS NOT NULL |
| else if (wordParser.startsWithIdentifier(NULL, index)) { |
| expression = new NullComparisonExpression(parent, IS_NOT_NULL, expression); |
| } |
| // IS NOT |
| else { |
| word = wordParser.substring(position, index - count); |
| expression = new UnknownExpression(parent, word); |
| } |
| } |
| // IS EMPTY |
| else if (wordParser.startsWithIdentifier(EMPTY, index)) { |
| expression = new EmptyCollectionComparisonExpression(parent, IS_EMPTY, expression); |
| } |
| // IS NULL |
| else if (wordParser.startsWithIdentifier(NULL, index)) { |
| expression = new NullComparisonExpression(parent, IS_NULL, expression); |
| } |
| // IS |
| else { |
| word = wordParser.substring(position, index - count); |
| expression = new UnknownExpression(parent, word); |
| } |
| |
| expression.parse(wordParser, tolerant); |
| return expression; |
| } |
| } |