1 /*

     2  * Copyright 2002 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  */

    23 

    24 import java.net.*;

    25 import java.util.*;

    26 import java.io.IOException;

    27 

    28 /**

    29  * This class provides a partial implementation of the HttpCallback

    30  * interface. Use this class if you want to use the requestURI as a means

    31  * of tracking multiple invocations of a request (on the server).

    32  * In this case, you implement the modified request() method, which includes

    33  * an integer count parameter. This parameter indicates the number of times

    34  * (starting at zero) the request URI has been received.

    35  */

    36 

    37 public abstract class AbstractCallback implements HttpCallback {

    38 

    39     Map requests;

    40 

    41     static class Request {

    42         URI uri;

    43         int count;

    44 

    45         Request (URI u) {

    46             uri = u;

    47             count = 0;

    48         }

    49     }

    50 

    51     AbstractCallback () {

    52         requests = Collections.synchronizedMap (new HashMap());

    53     }

    54 

    55     /**

    56      * handle the given request and generate an appropriate response.

    57      * @param msg the transaction containing the request from the

    58      *        client and used to send the response

    59      */

    60     public void request (HttpTransaction msg) {

    61         URI uri = msg.getRequestURI();

    62         Request req = (Request) requests.get (uri);

    63         if (req == null) {

    64             req = new Request (uri);

    65             requests.put (uri, req);

    66         }

    67         request (msg, req.count++);

    68     }

    69 

    70     /**

    71      * Same as HttpCallback interface except that the integer n

    72      * is provided to indicate sequencing of repeated requests using

    73      * the same request URI. n starts at zero and is incremented

    74      * for each successive call.

    75      *

    76      * @param msg the transaction containing the request from the

    77      *        client and used to send the response

    78      * @param n value is 0 at first call, and is incremented by 1 for

    79      *        each subsequent call using the same request URI.

    80      */

    81     abstract public void request (HttpTransaction msg, int n);

    82 }