1 /*
2 * ModeShape (http://www.modeshape.org)
3 * See the COPYRIGHT.txt file distributed with this work for information
4 * regarding copyright ownership. Some portions may be licensed
5 * to Red Hat, Inc. under one or more contributor license agreements.
6 * See the AUTHORS.txt file in the distribution for a full listing of
7 * individual contributors.
8 *
9 * ModeShape is free software. Unless otherwise indicated, all code in ModeShape
10 * is licensed to you under the terms of the GNU Lesser General Public License as
11 * published by the Free Software Foundation; either version 2.1 of
12 * the License, or (at your option) any later version.
13 *
14 * ModeShape is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with this software; if not, write to the Free
21 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
22 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
23 */
24 package org.modeshape.graph.query.process;
25
26 import java.util.List;
27 import org.modeshape.graph.query.model.Column;
28 import org.modeshape.graph.query.plan.PlanNode.Type;
29
30 /**
31 * A {@link ProcessingComponent} implementation that performs a {@link Type#PROJECT PROJECT} operation to reduce the columns that
32 * appear in the results.
33 */
34 public class ProjectComponent extends DelegatingComponent {
35
36 public ProjectComponent( ProcessingComponent delegate,
37 List<Column> columns ) {
38 super(delegate, delegate.getColumns().subSelect(columns));
39 }
40
41 /**
42 * {@inheritDoc}
43 *
44 * @see org.modeshape.graph.query.process.ProcessingComponent#execute()
45 */
46 @Override
47 public List<Object[]> execute() {
48 return delegate().execute();
49 }
50 }