| /* |
| * 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 java.util.List; |
| import org.eclipse.persistence.jpa.jpql.parser.GroupByClause; |
| import org.eclipse.persistence.jpa.jpql.parser.GroupByItemBNF; |
| import static org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.*; |
| |
| /** |
| * The <code><b>GROUP BY</b></code> construct enables the aggregation of values according to the |
| * properties of an entity class. |
| * |
| * <div><p><b>BNF:</b> <code>groupby_clause ::= GROUP BY groupby_item {, groupby_item}*</code></p></div> |
| * |
| * @see GroupByClause |
| * |
| * @version 2.4 |
| * @since 2.4 |
| * @author Pascal Filion |
| */ |
| @SuppressWarnings({"nls", "unused"}) // unused used for the import statement: see bug 330740 |
| public class GroupByClauseStateObject extends AbstractListHolderStateObject<StateObject> { |
| |
| /** |
| * Notify the list of {@link StateObject StateObjects} representing the <code><b>GROUP BY</b></code> |
| * items. |
| */ |
| public static final String GROUP_BY_ITEMS_LIST = "groupByItems"; |
| |
| /** |
| * Creates a new <code>GroupByClauseStateObject</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 GroupByClauseStateObject(AbstractSelectStatementStateObject parent) { |
| super(parent); |
| } |
| |
| @Override |
| public void accept(StateObjectVisitor visitor) { |
| visitor.visit(this); |
| } |
| |
| /** |
| * Adds the given path as a select item, which can either be an identification variable or a |
| * state-field path expression. |
| * |
| * @param path Either an identification variable or a state-field path expression |
| * @return The {@link StateObject} encapsulating the given path |
| */ |
| public StateObject addGroupByItem(String path) { |
| StateObject stateObject = buildStateObject(path, GroupByItemBNF.ID); |
| addItem(stateObject); |
| return stateObject; |
| } |
| |
| @Override |
| public GroupByClause getExpression() { |
| return (GroupByClause) super.getExpression(); |
| } |
| |
| @Override |
| public AbstractSelectStatementStateObject getParent() { |
| return (AbstractSelectStatementStateObject) super.getParent(); |
| } |
| |
| @Override |
| public boolean isEquivalent(StateObject stateObject) { |
| return super.isEquivalent(stateObject) && |
| areChildrenEquivalent((GroupByClauseStateObject) stateObject); |
| } |
| |
| @Override |
| protected String listName() { |
| return GROUP_BY_ITEMS_LIST; |
| } |
| |
| /** |
| * Parses the given JPQL fragment, which will represent the group by items. The fragment cannot |
| * start with the <code><b>GROUP BY</b></code>. |
| * |
| * @param jpqlFragment The string representation of the group by items |
| */ |
| public void parse(String jpqlFragment) { |
| List<StateObject> stateObjects = buildStateObjects(jpqlFragment, GroupByItemBNF.ID); |
| addItems(stateObjects); |
| } |
| |
| /** |
| * Keeps a reference of the {@link GroupByClause 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 GroupByClause parsed object} representing a <code><b>GROUP |
| * BY</b></code> clause |
| */ |
| public void setExpression(GroupByClause expression) { |
| super.setExpression(expression); |
| } |
| |
| @Override |
| protected void toTextInternal(Appendable writer) throws IOException { |
| writer.append(GROUP_BY); |
| if (hasItems()) { |
| writer.append(SPACE); |
| toStringItems(writer, true); |
| } |
| } |
| } |