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 package zeus.rete.action;
24 import zeus.rete.*;
25 import zeus.concepts.fn.*;
26 import zeus.concepts.*;
27 import zeus.util.*;
28 import java.util.*;
29 import java.io.*;
30 /***
31
32 @author Simon Thompson
33 @since 1.1
34 */
35 public class ReadlnAction extends ReteAction{
36
37 /***
38
39 */
40 public void executeAction (Action a, Info info) {
41 Hashtable readers = conflictHandler.getReaders();
42 ValueFunction var = ((ValueFunction)a.head).resolve(info.getBindings());
43 if ( var == null || var.getID() != ValueFunction.ID ) {
44 Core.USER_ERROR("Cannot resolve logical reader name '" + a.head + "' in action " + a);
45 return;
46 }
47 ValueFunction value = ((ValueFunction)a.sub_head).resolve(info.getBindings());
48 if ( value == null ) {
49 Core.USER_ERROR("Cannot resolve '" + a.sub_head + "' in action " + a);
50 return;
51 }
52
53 DataReader in = (DataReader)readers.get(((IdFn)var).getValue());
54 if ( in == null ) {
55 Core.USER_ERROR("Unknown reader '" + var + "' in " + a);
56 return;
57 }
58 try {
59 String input = null;
60 input = in.readLine();;
61 Bindings bind = info.getBindings();
62
63 if ( input == null )
64 Core.USER_ERROR("End of file reached while reading '" + var + "'");
65 else if ( Misc.isLong(input) )
66 bind.set(value,new IntFn(input));
67 else if ( Misc.isDouble(input) )
68 bind.set(value,new RealFn(input));
69 else
70 bind.set(value,new IdFn(input)); }
71 catch(IOException e) {
72 Core.USER_ERROR("IOException reading '" + var + "' in action " + a);
73 }
74 }
75
76
77 }