| /* |
| * 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.AbstractEncapsulatedExpression; |
| import static org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.*; |
| |
| /** |
| * This expression handles parsing the identifier followed by an expression encapsulated within |
| * parenthesis. |
| * |
| * <div><p><b>BNF:</b> <code>expression ::= <identifier>(expression)</code></p></div> |
| * |
| * @see AbstractEncapsulatedExpression |
| * |
| * @version 2.4 |
| * @since 2.4 |
| * @author Pascal Filion |
| */ |
| public abstract class AbstractEncapsulatedExpressionStateObject extends AbstractStateObject { |
| |
| /** |
| * Creates a new <code>AbstractEncapsulatedExpressionStateObject</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> |
| */ |
| protected AbstractEncapsulatedExpressionStateObject(StateObject parent) { |
| super(parent); |
| } |
| |
| @Override |
| public AbstractEncapsulatedExpression getExpression() { |
| return (AbstractEncapsulatedExpression) super.getExpression(); |
| } |
| |
| /** |
| * Returns the JPQL identifier of the expression represented by this {@link |
| * AbstractSingleEncapsulatedExpressionStateObject}. |
| * |
| * @return The JPQL identifier that is shown before the left parenthesis |
| */ |
| public abstract String getIdentifier(); |
| |
| /** |
| * Prints out a string representation of this encapsulated information, which should not be used |
| * to define a <code>true</code> string representation of a JPQL query but should be used for |
| * debugging purposes. |
| * |
| * @param writer The writer used to print out the string representation of the encapsulated |
| * information |
| * @throws IOException This should never happens, only required because {@link Appendable} is |
| * used instead of {@link StringBuilder} for instance |
| */ |
| protected abstract void toTextEncapsulatedExpression(Appendable writer) throws IOException; |
| |
| @Override |
| protected void toTextInternal(Appendable writer) throws IOException { |
| writer.append(getIdentifier()); |
| writer.append(LEFT_PARENTHESIS); |
| toTextEncapsulatedExpression(writer); |
| writer.append(RIGHT_PARENTHESIS); |
| } |
| } |