01: /******************************************************************
02: * File: addOne.java
03: * Created by: Dave Reynolds
04: * Created on: 11-Apr-2003
05: *
06: * (c) Copyright 2003, 2004, 2005, 2006, 2007, 2008 Hewlett-Packard Development Company, LP
07: * [See end of file]
08: * $Id: AddOne.java,v 1.10 2008/01/02 12:06:20 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:
14: /**
15: * Bind the second argument to 1+ the first argument. Just used for testing builtins.
16: *
17: * @author <a href="mailto:der@hplb.hpl.hp.com">Dave Reynolds</a>
18: * @version $Revision: 1.10 $ on $Date: 2008/01/02 12:06:20 $
19: */
20: public class AddOne extends BaseBuiltin {
21:
22: /**
23: * Return a name for this builtin, normally this will be the name of the
24: * functor that will be used to invoke it.
25: */
26: public String getName() {
27: return "addOne";
28: }
29:
30: /**
31: * Return the expected number of arguments for this functor or 0 if the number is flexible.
32: */
33: public int getArgLength() {
34: return 2;
35: }
36:
37: /**
38: * This method is invoked when the builtin is called in a rule body.
39: * @param args the array of argument values for the builtin, this is an array
40: * of Nodes, some of which may be Node_RuleVariables.
41: * @param context an execution context giving access to other relevant data
42: * @param length the length of the argument list, may be less than the length of the args array
43: * for some rule engines
44: * @return return true if the buildin predicate is deemed to have succeeded in
45: * the current environment
46: */
47: public boolean bodyCall(Node[] args, int length, RuleContext context) {
48: checkArgs(length, context);
49: BindingEnvironment env = context.getEnv();
50: boolean ok = false;
51: Node a0 = getArg(0, args, context);
52: Node a1 = getArg(1, args, context);
53: if (Util.isNumeric(a0)) {
54: Node newVal = Util.makeIntNode(Util.getIntValue(a0) + 1);
55: ok = env.bind(args[1], newVal);
56: } else if (Util.isNumeric(a1)) {
57: Node newVal = Util.makeIntNode(Util.getIntValue(a1) - 1);
58: ok = env.bind(args[0], newVal);
59: }
60: return ok;
61: }
62:
63: }
64:
65: /*
66: (c) Copyright 2003, 2004, 2005, 2006, 2007, 2008 Hewlett-Packard Development Company, LP
67: All rights reserved.
68:
69: Redistribution and use in source and binary forms, with or without
70: modification, are permitted provided that the following conditions
71: are met:
72:
73: 1. Redistributions of source code must retain the above copyright
74: notice, this list of conditions and the following disclaimer.
75:
76: 2. Redistributions in binary form must reproduce the above copyright
77: notice, this list of conditions and the following disclaimer in the
78: documentation and/or other materials provided with the distribution.
79:
80: 3. The name of the author may not be used to endorse or promote products
81: derived from this software without specific prior written permission.
82:
83: THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
84: IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
85: OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
86: IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
87: INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
88: NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
89: DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
90: THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
91: (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
92: THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
93: */
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