| /* |
| * Copyright (c) 2011, 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.tools.model.query; |
| |
| import java.io.IOException; |
| import org.eclipse.persistence.jpa.jpql.parser.ExistsExpression; |
| import org.eclipse.persistence.jpa.jpql.parser.SubqueryBNF; |
| import static org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.*; |
| |
| /** |
| * An <code><b>EXISTS</b></code> expression is a predicate that is <code>true</code> only if the |
| * result of the subquery consists of one or more values and that is <code>false</code> otherwise. |
| * |
| * <div><p><b>BNF:</b> <code>exists_expression ::= [NOT] EXISTS(subquery)</code></p></div> |
| * |
| * @see ExistsExpression |
| * |
| * @version 2.4 |
| * @since 2.4 |
| * @author Pascal Filion |
| */ |
| @SuppressWarnings({"nls", "unused"}) // unused used for the import statement: see bug 330740 |
| public class ExistsExpressionStateObject extends AbstractSingleEncapsulatedExpressionStateObject { |
| |
| /** |
| * Determines whether the <code><b>NOT</b></code> identifier is part of the expression or not. |
| */ |
| private boolean not; |
| |
| /** |
| * Notifies the visibility of the <code><b>NOT</b></code> identifier has changed. |
| */ |
| public static final String NOT_PROPERTY = "not"; |
| |
| /** |
| * Creates a new <code>ExistsExpressionStateObject</code>. |
| * |
| * @param parent The parent of this state object, which cannot be <code>null</code> |
| * @exception NullPointerException The given parent cannot be <code>null</code> |
| */ |
| public ExistsExpressionStateObject(StateObject parent) { |
| super(parent); |
| } |
| |
| /** |
| * Creates a new <code>ExistsExpressionStateObject</code>. |
| * |
| * @param parent The parent of this state object, which cannot be <code>null</code> |
| * @param not Determines whether the <code><b>NOT</b></code> identifier is part of the expression |
| * or not |
| * @param stateObject The {@link StateObject} representing the subquery |
| * @exception NullPointerException The given parent cannot be <code>null</code> |
| */ |
| public ExistsExpressionStateObject(StateObject parent, boolean not, StateObject stateObject) { |
| super(parent, stateObject); |
| this.not = not; |
| } |
| |
| /** |
| * Creates a new <code>ExistsExpressionStateObject</code>. |
| * |
| * @param parent The parent of this state object, which cannot be <code>null</code> |
| * @param not Determines whether the <code><b>NOT</b></code> identifier is part of the expression |
| * or not |
| * @param jpqlFragment The portion of the query representing the encapsulated expression |
| * @exception NullPointerException The given parent cannot be <code>null</code> |
| */ |
| public ExistsExpressionStateObject(StateObject parent, boolean not, String jpqlFragment) { |
| super(parent, jpqlFragment); |
| this.not = not; |
| } |
| |
| /** |
| * Creates a new <code>ExistsExpressionStateObject</code>. |
| * |
| * @param parent The parent of this state object, which cannot be <code>null</code> |
| * @param stateObject The {@link StateObject} representing the subquery |
| * @exception NullPointerException The given parent cannot be <code>null</code> |
| */ |
| public ExistsExpressionStateObject(StateObject parent, StateObject stateObject) { |
| this(parent, false, stateObject); |
| } |
| |
| /** |
| * Creates a new <code>ExistsExpressionStateObject</code>. |
| * |
| * @param parent The parent of this state object, which cannot be <code>null</code> |
| * @param jpqlFragment The portion of the query representing the encapsulated expression |
| * @exception NullPointerException The given parent cannot be <code>null</code> |
| */ |
| public ExistsExpressionStateObject(StateObject parent, String jpqlFragment) { |
| super(parent, jpqlFragment); |
| } |
| |
| @Override |
| public void accept(StateObjectVisitor visitor) { |
| visitor.visit(this); |
| } |
| |
| /** |
| * Makes sure the <code><b>NOT</b></code> identifier is specified. |
| * |
| * @return This object |
| */ |
| public ExistsExpressionStateObject addNot() { |
| if (!not) { |
| setNot(true); |
| } |
| return this; |
| } |
| |
| @Override |
| public ExistsExpression getExpression() { |
| return (ExistsExpression) super.getExpression(); |
| } |
| |
| @Override |
| public String getIdentifier() { |
| return EXISTS; |
| } |
| |
| @Override |
| protected String getQueryBNFId() { |
| return SubqueryBNF.ID; |
| } |
| |
| /** |
| * Determines whether the <code><b>NOT</b></code> identifier is used or not. |
| * |
| * @return <code>true</code> if the <code><b>NOT</b></code> identifier is part of the expression; |
| * <code>false</code> otherwise |
| */ |
| public boolean hasNot() { |
| return not; |
| } |
| |
| @Override |
| public boolean isEquivalent(StateObject stateObject) { |
| |
| if (super.isEquivalent(stateObject)) { |
| ExistsExpressionStateObject exists = (ExistsExpressionStateObject) stateObject; |
| return not == exists.not; |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Makes sure the <code><b>NOT</b></code> identifier is not specified. |
| */ |
| public void removeNot() { |
| if (not) { |
| setNot(false); |
| } |
| } |
| |
| /** |
| * Keeps a reference of the {@link ExistsExpression parsed object} object, which should only be |
| * done when this object is instantiated during the conversion of a parsed JPQL query into |
| * {@link StateObject StateObjects}. |
| * |
| * @param expression The {@link ExistsExpression parsed object} representing an <code><b>EXISTS</b></code> |
| * expression |
| */ |
| public void setExpression(ExistsExpression expression) { |
| super.setExpression(expression); |
| } |
| |
| /** |
| * Sets whether the <code><b>NOT</b></code> identifier should be part of the expression or not. |
| * |
| * @param not <code>true</code> if the <code><b>NOT</b></code> identifier should be part of the |
| * expression; <code>false</code> otherwise |
| */ |
| public void setNot(boolean not) { |
| boolean oldNot = this.not; |
| this.not = not; |
| firePropertyChanged(NOT_PROPERTY, oldNot, not); |
| } |
| |
| @Override |
| public void setStateObject(StateObject stateObject) { |
| super.setStateObject(stateObject); |
| } |
| |
| /** |
| * Changes the visibility state of the <code><b>NOT</b></code> identifier. |
| */ |
| public void toggleNot() { |
| setNot(!not); |
| } |
| |
| @Override |
| protected void toTextEncapsulatedExpression(Appendable writer) throws IOException { |
| writer.append(not ? NOT_EXISTS : EXISTS); |
| writer.append(LEFT_PARENTHESIS); |
| super.toTextEncapsulatedExpression(writer); |
| writer.append(RIGHT_PARENTHESIS); |
| } |
| } |