| /* |
| * 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 java.util.Collection; |
| import java.util.List; |
| import org.eclipse.persistence.jpa.jpql.Assert; |
| import org.eclipse.persistence.jpa.jpql.WordParser; |
| |
| /** |
| * This expression handles parsing a JPQL identifier followed by an expression encapsulated within |
| * parenthesis. |
| * |
| * <div><b>BNF:</b> <code>expression ::= <identifier>(expression)</code></div> |
| * |
| * @version 2.5 |
| * @since 2.3 |
| * @author Pascal Filion |
| */ |
| @SuppressWarnings("nls") |
| public abstract class AbstractSingleEncapsulatedExpression extends AbstractEncapsulatedExpression { |
| |
| /** |
| * The sub-expression encapsulated within parenthesis. |
| */ |
| private AbstractExpression expression; |
| |
| /** |
| * Creates a new <code>EncapsulatedExpression</code>. |
| * |
| * @param parent The parent of this expression |
| * @param identifier The JPQL identifier that starts this expression |
| */ |
| protected AbstractSingleEncapsulatedExpression(AbstractExpression parent, String identifier) { |
| super(parent, identifier); |
| } |
| |
| @Override |
| public void acceptChildren(ExpressionVisitor visitor) { |
| getExpression().accept(visitor); |
| } |
| |
| @Override |
| protected final void addChildrenTo(Collection<Expression> children) { |
| children.add(getExpression()); |
| } |
| |
| @Override |
| protected void addOrderedEncapsulatedExpressionTo(List<Expression> children) { |
| if (expression != null) { |
| children.add(expression); |
| } |
| } |
| |
| @Override |
| public JPQLQueryBNF findQueryBNF(Expression expression) { |
| |
| if ((expression != null) && expression.isAncestor(expression)) { |
| return getQueryBNF(getEncapsulatedExpressionQueryBNFId()); |
| } |
| |
| return super.findQueryBNF(expression); |
| } |
| |
| /** |
| * Returns the BNF used to parse the encapsulated expression. |
| * |
| * @return The BNF used to parse the encapsulated expression |
| */ |
| public abstract String getEncapsulatedExpressionQueryBNFId(); |
| |
| /** |
| * Returns the {@link Expression} that is encapsulated within parenthesis. |
| * |
| * @return The {@link Expression} that is encapsulated within parenthesis |
| */ |
| public final Expression getExpression() { |
| if (expression == null) { |
| expression = buildNullExpression(); |
| } |
| return expression; |
| } |
| |
| @Override |
| public boolean hasEncapsulatedExpression() { |
| return hasExpression(); |
| } |
| |
| /** |
| * Determines whether the encapsulated expression of the query was parsed. |
| * |
| * @return <code>true</code> if the encapsulated expression was parsed; <code>false</code> if it |
| * was not parsed |
| */ |
| public final boolean hasExpression() { |
| return expression != null && |
| !expression.isNull(); |
| } |
| |
| @Override |
| protected void parseEncapsulatedExpression(WordParser wordParser, |
| int whitespaceCount, |
| boolean tolerant) { |
| |
| expression = parse(wordParser, getEncapsulatedExpressionQueryBNFId(), tolerant); |
| } |
| |
| @Override |
| protected void removeEncapsulatedExpression() { |
| expression = null; |
| } |
| |
| /** |
| * Manually sets the encapsulated {@link Expression} to become the given one. |
| * |
| * @param expression The new encapsulated {@link Expression}, which cannot be <code>null</code> |
| * @exception NullPointerException The given {@link AbstractExpression} cannot be <code>null</code> |
| */ |
| public final void setExpression(AbstractExpression expression) { |
| Assert.isNotNull(expression, "The Expression cannot be null"); |
| this.expression = expression; |
| this.expression.setParent(this); |
| } |
| |
| @Override |
| protected void toParsedTextEncapsulatedExpression(StringBuilder writer, boolean actual) { |
| if (expression != null) { |
| expression.toParsedText(writer, actual); |
| } |
| } |
| } |