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.model.NodePointer;
22
23 /**
24 * A single-set EvalContext that provides access to the current node of
25 * the parent context and nothing else. It does not pass the iteration
26 * on to the parent context.
27 *
28 * @author Dmitri Plotnikov
29 * @version $Revision: 652845 $ $Date: 2008-05-02 19:46:46 +0200 (Fr, 02 Mai 2008) $
30 */
31 public class InitialContext extends EvalContext {
32 private boolean started = false;
33 private boolean collection;
34 private NodePointer nodePointer;
35
36 /**
37 * Create a new InitialContext.
38 * @param parentContext parent context
39 */
40 public InitialContext(EvalContext parentContext) {
41 super(parentContext);
42 nodePointer =
43 (NodePointer) parentContext.getCurrentNodePointer().clone();
44 if (nodePointer != null) {
45 collection =
46 (nodePointer.getIndex() == NodePointer.WHOLE_COLLECTION);
47 }
48 }
49
50 public Pointer getSingleNodePointer() {
51 return nodePointer;
52 }
53
54 public NodePointer getCurrentNodePointer() {
55 return nodePointer;
56 }
57
58 public Object getValue() {
59 return nodePointer.getValue();
60 }
61
62 public boolean nextNode() {
63 return setPosition(position + 1);
64 }
65
66 public boolean setPosition(int position) {
67 this.position = position;
68 if (collection) {
69 if (position >= 1 && position <= nodePointer.getLength()) {
70 nodePointer.setIndex(position - 1);
71 return true;
72 }
73 return false;
74 }
75 return position == 1;
76 }
77
78 public boolean nextSet() {
79 if (started) {
80 return false;
81 }
82 started = true;
83 return true;
84 }
85 }