1 /*
2 * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/expr/Step.java,v 1.9 2005/06/28 13:44:44 elharo Exp $
3 * $Revision: 1.9 $
4 * $Date: 2005/06/28 13:44:44 $
5 *
6 * ====================================================================
7 *
8 * Copyright (C) 2000-2002 bob mcwhirter & James Strachan.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 *
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer.
17 *
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions, and the disclaimer that follows
20 * these conditions in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * 3. The name "Jaxen" must not be used to endorse or promote products
24 * derived from this software without prior written permission. For
25 * written permission, please contact license@jaxen.org.
26 *
27 * 4. Products derived from this software may not be called "Jaxen", nor
28 * may "Jaxen" appear in their name, without prior written permission
29 * from the Jaxen Project Management (pm@jaxen.org).
30 *
31 * In addition, we request (but do not require) that you include in the
32 * end-user documentation provided with the redistribution and/or in the
33 * software itself an acknowledgement equivalent to the following:
34 * "This product includes software developed by the
35 * Jaxen Project <http://www.jaxen.org/>."
36 * Alternatively, the acknowledgment may be graphical using the logos
37 * available at http://www.jaxen.org/
38 *
39 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
40 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
41 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
42 * DISCLAIMED. IN NO EVENT SHALL THE Jaxen AUTHORS OR THE PROJECT
43 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
45 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
46 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
47 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
48 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
49 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50 * SUCH DAMAGE.
51 *
52 * ====================================================================
53 * This software consists of voluntary contributions made by many
54 * individuals on behalf of the Jaxen Project and was originally
55 * created by bob mcwhirter <bob@werken.com> and
56 * James Strachan <jstrachan@apache.org>. For more information on the
57 * Jaxen Project, please see <http://www.jaxen.org/>.
58 *
59 * $Id: Step.java,v 1.9 2005/06/28 13:44:44 elharo Exp $
60 */
61
62 package org.jaxen.expr;
63
64 import java.util.Iterator;
65 import java.util.List;
66
67 import org.jaxen.Context;
68 import org.jaxen.ContextSupport;
69 import org.jaxen.JaxenException;
70 import org.jaxen.UnsupportedAxisException;
71
72 /***
73 * A Step represents a location step in a LocationPath. The node-set selected by
74 * the location step is the node-set that results from generating an initial
75 * node-set from the axis and node-test, and then filtering that node-set by
76 * each of the predicates in turn.
77 *
78 * The initial node-set consists of the nodes having the relationship to the
79 * context node specified by the axis, and having the node type and expanded-name
80 * specified by the node test.
81 */
82 public interface Step extends Predicated, Visitable
83 {
84
85 /***
86 * Performs the node-test part of evaluating the step for the given node
87 * (which must be on the axis).
88 */
89 boolean matches(Object node,
90 ContextSupport contextSupport) throws JaxenException;
91
92 String getText();
93
94 void simplify();
95
96 /***
97 * Get an identifier for the current axis.
98 * @see org.jaxen.saxpath.Axis
99 */
100 public int getAxis();
101
102 /***
103 * Get an Iterator for the current axis starting in the given contextNode.
104 */
105 Iterator axisIterator(Object contextNode,
106 ContextSupport support) throws UnsupportedAxisException;
107
108 /***
109 * For each node in the given context calls matches() for every node on the
110 * axis, then filters the result by each of the predicates.
111 */
112 List evaluate(Context context) throws JaxenException;
113
114 }
115