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1   /*
2   * The contents of this file are subject to the BT "ZEUS" Open Source 
3   * Licence (L77741), Version 1.0 (the "Licence"); you may not use this file 
4   * except in compliance with the Licence. You may obtain a copy of the Licence
5   * from $ZEUS_INSTALL/licence.html or alternatively from
6   * http://www.labs.bt.com/projects/agents/zeus/licence.htm
7   * 
8   * Except as stated in Clause 7 of the Licence, software distributed under the
9   * Licence is distributed WITHOUT WARRANTY OF ANY KIND, either express or 
10  * implied. See the Licence for the specific language governing rights and 
11  * limitations under the Licence.
12  * 
13  * The Original Code is within the package zeus.*.
14  * The Initial Developer of the Original Code is British Telecommunications
15  * public limited company, whose registered office is at 81 Newgate Street, 
16  * London, EC1A 7AJ, England. Portions created by British Telecommunications 
17  * public limited company are Copyright 1996-9. All Rights Reserved.
18  * 
19  * THIS NOTICE MUST BE INCLUDED ON ANY COPY OF THIS FILE
20  */
21  
22  
23  
24  package zeus.actors.rtn;
25  
26  import java.util.*;
27  import zeus.util.*;
28  import zeus.actors.AgentContext;
29  
30  public class Arc {
31     private  static int count = 0;
32  
33     protected String       description = null;
34     protected Object       output = null;
35     protected Object       input = null;
36     protected AgentContext context = null;
37     protected Graph        graph = null;
38  
39     protected Arc() {
40     }
41     public Arc(String description) {
42        Assert.notNull(description);
43        this.description = description + "-" + (count++);
44        Core.DEBUG(3,"New arc " + this.description + " created");
45     }
46  
47     public final String getDescription() { return description; }
48     public final Graph  getGraph()       { return graph; }
49  
50     void run1(Engine engine, Graph graph, Node previous_node,
51               Object input, String next_node) {
52  
53        this.input = input;
54        this.graph = graph;
55        context = engine.getAgentContext();
56  
57        Node node = null;
58        if ( exec() && (node = graph.newNode(engine,next_node,previous_node)) != null ) {
59           node.setInput(engine,output);
60           engine.notifyArcMonitors(this,node,Engine.ARC_SUCCEED);
61           engine.add(node);
62        }
63        else {
64           Core.DEBUG(3,"Arc " + description + " FAILED");
65           engine.notifyArcMonitors(this,null,Engine.ARC_FAIL);
66           previous_node.nextArc(engine);
67        }
68     }
69     protected boolean exec() {
70        output = input;
71        return true;
72     }
73     protected void finalize() throws Throwable {
74        if ( context != null )
75           context.Engine().notifyArcMonitors(this,null,Engine.ARC_DISPOSE);
76        super.finalize();
77     }
78     public String toString() { return getDescription(); }
79  }