| /* |
| * Copyright (c) 2012, 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.ArrayList; |
| import java.util.Collection; |
| import java.util.List; |
| import org.eclipse.persistence.jpa.jpql.WordParser; |
| |
| /** |
| * An ordering clause allows the objects or values that are returned by the query to be ordered. |
| * |
| * <div><b>BNF:</b> <code>orderby_clause ::= <b><identifier></b> {@link OrderByItem orderby_item} {, {@link OrderByItem orderby_item}}*</code></div> |
| * |
| * @version 2.5 |
| * @since 2.5 |
| * @author Pascal Filion |
| */ |
| public abstract class AbstractOrderByClause extends AbstractExpression { |
| |
| /** |
| * Determines whether a whitespace was parsed after the JPQL identifier. |
| */ |
| private boolean hasSpaceAfterIdentifier; |
| |
| /** |
| * The actual identifier found in the string representation of the JPQL query. |
| */ |
| private String identifier; |
| |
| /** |
| * The order by items. |
| */ |
| private AbstractExpression orderByItems; |
| |
| /** |
| * Creates a new <code>AbstractOrderByClause</code>. |
| * |
| * @param parent The parent of this expression |
| * @param identifier The JPQL identifier representing an ordering clause |
| */ |
| protected AbstractOrderByClause(AbstractExpression parent, String identifier) { |
| super(parent, identifier); |
| } |
| |
| @Override |
| public void acceptChildren(ExpressionVisitor visitor) { |
| getOrderByItems().accept(visitor); |
| } |
| |
| @Override |
| protected void addChildrenTo(Collection<Expression> children) { |
| children.add(getOrderByItems()); |
| } |
| |
| @Override |
| protected void addOrderedChildrenTo(List<Expression> children) { |
| |
| children.add(buildStringExpression(getText())); |
| |
| if (hasSpaceAfterIdentifier) { |
| children.add(buildStringExpression(SPACE)); |
| } |
| |
| if (orderByItems != null) { |
| children.add(orderByItems); |
| } |
| } |
| |
| /** |
| * Creates a new {@link CollectionExpression} that will wrap the single order by item. |
| * |
| * @return The single order by item represented by a temporary collection |
| */ |
| public final CollectionExpression buildCollectionExpression() { |
| |
| List<AbstractExpression> children = new ArrayList<>(1); |
| children.add((AbstractExpression) getOrderByItems()); |
| |
| List<Boolean> commas = new ArrayList<>(1); |
| commas.add(Boolean.FALSE); |
| |
| List<Boolean> spaces = new ArrayList<>(1); |
| spaces.add(Boolean.FALSE); |
| |
| return new CollectionExpression(this, children, spaces, commas, true); |
| } |
| |
| @Override |
| public final JPQLQueryBNF findQueryBNF(Expression expression) { |
| |
| if ((orderByItems != null) && orderByItems.isAncestor(expression)) { |
| return getQueryBNF(OrderByItemBNF.ID); |
| } |
| |
| return super.findQueryBNF(expression); |
| } |
| |
| /** |
| * Returns the actual identifier found in the string representation of the JPQL query, which |
| * has the actual case that was used. |
| * |
| * @return The actual identifier that was actually parsed |
| */ |
| public final String getActualIdentifier() { |
| return identifier; |
| } |
| |
| /** |
| * Returns the {@link Expression} representing the list of items to order. |
| * |
| * @return The expression representing the list of items to order |
| */ |
| public final Expression getOrderByItems() { |
| if (orderByItems == null) { |
| orderByItems = buildNullExpression(); |
| } |
| return orderByItems; |
| } |
| |
| /** |
| * Determines whether the list of items to order was parsed. |
| * |
| * @return <code>true</code> the list of items to order was parsed; <code>false</code> otherwise |
| */ |
| public final boolean hasOrderByItems() { |
| return orderByItems != null && |
| !orderByItems.isNull(); |
| } |
| |
| /** |
| * Determines whether a whitespace was parsed after the identifier. |
| * |
| * @return <code>true</code> if a whitespace was parsed after the identifier; <code>false</code> otherwise |
| */ |
| public final boolean hasSpaceAfterIdentifier() { |
| return hasSpaceAfterIdentifier; |
| } |
| |
| @Override |
| protected void parse(WordParser wordParser, boolean tolerant) { |
| |
| // Identifier |
| identifier = wordParser.moveForwardIgnoreWhitespace(getText()); |
| |
| hasSpaceAfterIdentifier = wordParser.skipLeadingWhitespace() > 0; |
| |
| // Group by items |
| orderByItems = parse(wordParser, OrderByItemBNF.ID, tolerant); |
| } |
| |
| @Override |
| protected void toParsedText(StringBuilder writer, boolean actual) { |
| |
| // Identifier |
| writer.append(actual ? identifier : getText()); |
| |
| if (hasSpaceAfterIdentifier) { |
| writer.append(SPACE); |
| } |
| |
| // Order by items |
| if (orderByItems != null) { |
| orderByItems.toParsedText(writer, actual); |
| } |
| } |
| } |