| /* |
| * 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; |
| |
| /** |
| * Only the values of like types are permitted to be compared. A type is like another type if they |
| * correspond to the same Java language type, or if one is a primitive Java language type and the |
| * other is the wrapped Java class type equivalent (e.g., int and Integer are like types in this |
| * sense). |
| * <p> |
| * There is one exception to this rule: it is valid to compare numeric values for which the rules of |
| * numeric promotion apply. Conditional expressions attempting to compare non-like type values are |
| * disallowed except for this numeric case. |
| * <p> |
| * Note that the arithmetic operators and comparison operators are permitted to be applied to |
| * state-fields and input parameters of the wrapped Java class equivalents to the primitive numeric |
| * Java types. Two entities of the same abstract schema type are equal if and only if they have the |
| * same primary key value. Only equality/inequality comparisons over enumeration constants are |
| * required to be supported. |
| * <p> |
| * <b>JPA 1.0 - BNF:</b> |
| * <pre><code>comparison_expression ::= string_expression comparison_operator {string_expression | all_or_any_expression} | |
| * boolean_expression {=|{@literal <>}} {boolean_expression | all_or_any_expression} | |
| * enum_expression {=|{@literal <>}} {enum_expression | all_or_any_expression} | |
| * datetime_expression comparison_operator {datetime_expression | all_or_any_expression} | |
| * entity_expression {=|{@literal <>}} {entity_expression | all_or_any_expression} | |
| * arithmetic_expression comparison_operator {arithmetic_expression | all_or_any_expression}</code></pre> |
| * |
| * <b>JPA 2.0 - BNF:</b> |
| * <pre><code>comparison_expression ::= string_expression comparison_operator {string_expression | all_or_any_expression} | |
| * boolean_expression {=|{@literal <>}} {boolean_expression | all_or_any_expression} | |
| * enum_expression {=|{@literal <>}} {enum_expression | all_or_any_expression} | |
| * datetime_expression comparison_operator {datetime_expression | all_or_any_expression} | |
| * entity_expression {=|{@literal <>}} {entity_expression | all_or_any_expression} | |
| * arithmetic_expression comparison_operator {arithmetic_expression | all_or_any_expression} | |
| * <b>entity_type_expression {=|{@literal <>}} entity_type_expression}</b></code></pre> |
| * |
| * @version 2.5 |
| * @since 2.3 |
| * @author Pascal Filion |
| */ |
| public final class ComparisonExpression extends CompoundExpression { |
| |
| /** |
| * Creates a new <code>ComparisonExpression</code>. |
| * |
| * @param parent The parent of this expression |
| * @param identifier The comparator identifier |
| */ |
| public ComparisonExpression(AbstractExpression parent, String identifier) { |
| super(parent, identifier); |
| } |
| |
| @Override |
| public void accept(ExpressionVisitor visitor) { |
| visitor.visit(this); |
| } |
| |
| /** |
| * Returns the comparison operator, which is either {@literal '=', '>', '>=', '<', '<=' or '<>'}. |
| * |
| * @return The operator comparing the two expressions |
| */ |
| public String getComparisonOperator() { |
| return getText(); |
| } |
| |
| @Override |
| public String getLeftExpressionQueryBNFId() { |
| return ComparisonExpressionBNF.ID; |
| } |
| |
| @Override |
| public JPQLQueryBNF getQueryBNF() { |
| return getQueryBNF(ComparisonExpressionBNF.ID); |
| } |
| |
| @Override |
| public String getRightExpressionQueryBNFId() { |
| return ComparisonExpressionBNF.ID; |
| } |
| |
| @Override |
| protected boolean isParsingComplete(WordParser wordParser, String word, Expression expression) { |
| |
| // TODO: This should be handled differently since it has the knowledge of parent expression |
| return wordParser.character() == RIGHT_PARENTHESIS || |
| |
| // This happens when parsing a logical expression |
| word.equalsIgnoreCase(OR) || |
| word.equalsIgnoreCase(AND) || |
| |
| // This happens when parsing a conditional expression in a CASE expression |
| word.equalsIgnoreCase(WHEN) || |
| word.equalsIgnoreCase(THEN) || |
| word.equalsIgnoreCase(ELSE) || |
| word.equalsIgnoreCase(END) || |
| |
| // This happens when parsing a conditional expression in a join condition |
| word.equalsIgnoreCase(LEFT) || |
| word.equalsIgnoreCase(OUTER) || |
| word.equalsIgnoreCase(INNER) || |
| word.equalsIgnoreCase(JOIN) || |
| |
| super.isParsingComplete(wordParser, word, expression); |
| } |
| |
| @Override |
| protected String parseIdentifier(WordParser wordParser) { |
| return getText(); |
| } |
| } |