1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.jxpath.ri.axes;
18
19 import org.apache.commons.jxpath.Pointer;
20 import org.apache.commons.jxpath.ri.EvalContext;
21 import org.apache.commons.jxpath.ri.compiler.NodeTest;
22 import org.apache.commons.jxpath.ri.model.NodePointer;
23
24 /**
25 * EvalContext that returns the current node from the parent context if the
26 * test succeeds.
27 *
28 * @author Dmitri Plotnikov
29 * @version $Revision: 1523199 $ $Date: 2013-09-14 11:45:47 +0200 (Sa, 14 Sep 2013) $
30 */
31 public class SelfContext extends EvalContext {
32 private NodeTest nodeTest;
33 private boolean startedSet = false;
34 private NodePointer nodePointer;
35
36 /**
37 * Create a new SelfContext.
38 * @param parentContext EvalContext
39 * @param nodeTest guard
40 */
41 public SelfContext(EvalContext parentContext, NodeTest nodeTest) {
42 super(parentContext);
43 this.nodeTest = nodeTest;
44 }
45
46 public Pointer getSingleNodePointer() {
47 return parentContext.getSingleNodePointer();
48 }
49
50 public NodePointer getCurrentNodePointer() {
51 if (position == 0 && !setPosition(1)) {
52 return null;
53 }
54 return nodePointer;
55 }
56
57 public boolean nextNode() {
58 return setPosition(getCurrentPosition() + 1);
59 }
60
61 public void reset() {
62 super.reset();
63 startedSet = false;
64 }
65
66 public boolean setPosition(int position) {
67 if (position != 1) {
68 return false;
69 }
70 super.setPosition(position);
71 if (!startedSet) {
72 startedSet = true;
73 nodePointer = parentContext.getCurrentNodePointer();
74 }
75
76 if (nodePointer == null) {
77 return false;
78 }
79
80 return nodeTest == null || nodePointer.testNode(nodeTest);
81 }
82 }