| /* |
| * 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 ComparisonExpressionFactory} creates a new {@link ComparisonExpression} when the |
| * portion of the query to parse starts with <b><</b>, <b>></b>, <b>{@literal <>}</b>, <b><=</b>, |
| * <b>>=</b> or <b>=</b>. |
| * |
| * @see ComparisonExpression |
| * |
| * @version 2.4 |
| * @since 2.3 |
| * @author Pascal Filion |
| */ |
| @SuppressWarnings("nls") |
| public final class ComparisonExpressionFactory extends ExpressionFactory { |
| |
| /** |
| * The unique identifier of this {@link ComparisonExpressionFactory}. |
| */ |
| public static final String ID = "comparison"; |
| |
| /** |
| * Creates a new <code>ComparisonExpressionFactory</code>. |
| */ |
| public ComparisonExpressionFactory() { |
| super(ID, DIFFERENT, |
| EQUAL, |
| GREATER_THAN, |
| GREATER_THAN_OR_EQUAL, |
| LOWER_THAN, |
| LOWER_THAN_OR_EQUAL); |
| } |
| |
| @Override |
| protected AbstractExpression buildExpression(AbstractExpression parent, |
| WordParser wordParser, |
| String word, |
| JPQLQueryBNF queryBNF, |
| AbstractExpression expression, |
| boolean tolerant) { |
| |
| String operator = null; |
| |
| // First look for known operator (<, <=, =, =>, <>) |
| switch (wordParser.character()) { |
| |
| // <, <=, <> |
| case '<': { |
| switch (wordParser.character(wordParser.position() + 1)) { |
| case '=': { |
| operator = LOWER_THAN_OR_EQUAL; |
| break; |
| } |
| case '>': { |
| operator = DIFFERENT; |
| break; |
| } |
| default: { |
| operator = LOWER_THAN; |
| break; |
| } |
| } |
| break; |
| } |
| |
| // >, >= |
| case '>': { |
| switch (wordParser.character(wordParser.position() + 1)) { |
| case '=': { |
| operator = GREATER_THAN_OR_EQUAL; |
| break; |
| } |
| default: { |
| operator = GREATER_THAN; |
| break; |
| } |
| } |
| break; |
| } |
| |
| // = |
| case '=': { |
| operator = EQUAL; |
| break; |
| } |
| } |
| |
| // Now look for additional identifiers |
| if (operator == null) { |
| for (String identifier : identifiers()) { |
| if (wordParser.startsWith(identifier)) { |
| operator = identifier; |
| break; |
| } |
| } |
| } |
| |
| // The operator was found, create the expression |
| if (operator != null) { |
| |
| ComparisonExpression comparisonExpression = new ComparisonExpression(parent, operator); |
| comparisonExpression.parse(wordParser, tolerant); |
| |
| if (expression != null) { |
| comparisonExpression.setLeftExpression(expression); |
| } |
| |
| return comparisonExpression; |
| } |
| |
| return null; |
| } |
| } |