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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  package zeus.actors.factories; 
22  import zeus.actors.OutTray; 
23  import zeus.util.SystemProps;
24  
25  public class ConnectionPool {
26      
27      public int MAX_CONNECTIONS = Integer.parseInt(SystemProps.getProperty("num.connections")); 
28      private OutTray[] connections = new OutTray[MAX_CONNECTIONS]; 
29      private String[] keys = new String [MAX_CONNECTIONS]; 
30      private int write = 0; 
31      
32      
33      /*** 
34          get a connection from the connection pool. Throw an exception if it is
35          not present
36          */
37      public OutTray getConnection (String address) throws NotFoundException { 
38         for (int i = 0; i < MAX_CONNECTIONS ; i++) {
39          
40          if (keys[i]== null) { ;}
41          else { 
42             // System.out.println("keys[i] == " + keys[i] + " address == " + address); 
43              if (keys[i].equals(address)) { 
44                  return (connections[i]); 
45              }
46          }
47          //System.out.println(i); 
48          }
49         throw new NotFoundException(); 
50      
51      }
52      
53      
54      /*** 
55          store a connection in the pool. If more than MAX_CONNECTIONS then eliminate the 
56          oldest - doesn't check to see if connection is in here!*/ 
57      public void addConnection (String address, OutTray connection) { 
58          if (write >= MAX_CONNECTIONS){
59              write = 0; 
60          }
61       //   System.out.println("setting address = " + address); 
62          connections[write] = connection; 
63          keys[write] = address; 
64          write ++; 
65      }
66              
67      
68  }