01: /*
02: (c) Copyright 2002, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Hewlett-Packard Development Company, LP
03: [See end of file]
04: $Id: InitialStage.java,v 1.14 2008/01/02 12:07:57 andy_seaborne Exp $
05: */
06:
07: package com.hp.hpl.jena.graph.query;
08:
09: /**
10: The initial stage of a query, responsible for dropping the no-variables-bound seed
11: binding domain into the remaining stages of the query pipeline.
12:
13: @author kers
14: */
15: public class InitialStage extends Stage {
16: /**
17: The value passed in is the computed width of the result array(s); this
18: is used to allocate the seeding node array.
19:
20: @param count the width of the result binding array
21: */
22: public InitialStage(int count) {
23: this .count = count;
24: }
25:
26: final int count;
27:
28: public void close() {
29: markClosed();
30: }
31:
32: /**
33: To deliver value into the Pipe result, we drop in a binding array of the correct
34: width in which all the elements are null, then we close the pipe. Everything else
35: is spawned by the following stages.
36: */
37: public Pipe deliver(Pipe result) {
38: result.put(new Domain(count));
39: result.close();
40: return result;
41: }
42: }
43:
44: /*
45: (c) Copyright 2002, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Hewlett-Packard Development Company, LP
46: All rights reserved.
47:
48: Redistribution and use in source and binary forms, with or without
49: modification, are permitted provided that the following conditions
50: are met:
51:
52: 1. Redistributions of source code must retain the above copyright
53: notice, this list of conditions and the following disclaimer.
54:
55: 2. Redistributions in binary form must reproduce the above copyright
56: notice, this list of conditions and the following disclaimer in the
57: documentation and/or other materials provided with the distribution.
58:
59: 3. The name of the author may not be used to endorse or promote products
60: derived from this software without specific prior written permission.
61:
62: THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
63: IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
64: OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
65: IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
66: INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
67: NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
68: DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
69: THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
70: (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
71: THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
72: */
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