01: /******************************************************************
02: * File: ListMapAsSubject.java
03: * Created by: Dave Reynolds
04: * Created on: 23-Sep-2003
05: *
06: * (c) Copyright 2003, 2004, 2005, 2006, 2007, 2008 Hewlett-Packard Development Company, LP, all rights reserved.
07: * [See end of file]
08: * $Id: ListMapAsSubject.java,v 1.9 2008/01/02 12:06:22 andy_seaborne Exp $
09: *****************************************************************/package com.hp.hpl.jena.reasoner.rulesys.builtins;
10:
11: import com.hp.hpl.jena.reasoner.rulesys.*;
12: import com.hp.hpl.jena.graph.*;
13: import java.util.*;
14:
15: /**
16: * For each element in the RDF list (first argument) it asserts
17: * triples with that as the subject and predicate and object given by arguments
18: * two and three. A strange and hacky function, only usable in the head of
19: * forward rules.
20: *
21: * @author <a href="mailto:der@hplb.hpl.hp.com">Dave Reynolds</a>
22: * @version $Revision: 1.9 $ on $Date: 2008/01/02 12:06:22 $
23: */
24: public class ListMapAsSubject extends BaseBuiltin {
25:
26: /**
27: * Return a name for this builtin, normally this will be the name of the
28: * functor that will be used to invoke it.
29: */
30: public String getName() {
31: return "listMapAsSubject";
32: }
33:
34: /**
35: * Return the expected number of arguments for this functor or 0 if the number is flexible.
36: */
37: public int getArgLength() {
38: return 3;
39: }
40:
41: /**
42: * This method is invoked when the builtin is called in a rule head.
43: * Such a use is only valid in a forward rule.
44: * @param args the array of argument values for the builtin, this is an array
45: * of Nodes.
46: * @param length the length of the argument list, may be less than the length of the args array
47: * for some rule engines
48: * @param context an execution context giving access to other relevant data
49: */
50: public void headAction(Node[] args, int length, RuleContext context) {
51: checkArgs(length, context);
52: Node n0 = getArg(0, args, context);
53: Node n1 = getArg(1, args, context);
54: Node n2 = getArg(2, args, context);
55: List l = Util.convertList(n0, context);
56: for (Iterator i = l.iterator(); i.hasNext();) {
57: Node x = (Node) i.next();
58: context.add(new Triple(x, n1, n2));
59: }
60: }
61:
62: }
63:
64: /*
65: (c) Copyright 2003, 2004, 2005, 2006, 2007, 2008 Hewlett-Packard Development Company, LP
66: All rights reserved.
67:
68: Redistribution and use in source and binary forms, with or without
69: modification, are permitted provided that the following conditions
70: are met:
71:
72: 1. Redistributions of source code must retain the above copyright
73: notice, this list of conditions and the following disclaimer.
74:
75: 2. Redistributions in binary form must reproduce the above copyright
76: notice, this list of conditions and the following disclaimer in the
77: documentation and/or other materials provided with the distribution.
78:
79: 3. The name of the author may not be used to endorse or promote products
80: derived from this software without specific prior written permission.
81:
82: THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
83: IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
84: OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
85: IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
86: INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
87: NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
88: DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
89: THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
90: (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
91: THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
92: */
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