/* 
    P/P   *  Method: net.sourceforge.pebble.confirmation.SimpleMathsConfirmationStrategy__static_init
          */
     1  /*
     2   * Copyright (c) 2003-2006, Simon Brown
     3   * All rights reserved.
     4   *
     5   * Redistribution and use in source and binary forms, with or without
     6   * modification, are permitted provided that the following conditions are met:
     7   *
     8   *   - Redistributions of source code must retain the above copyright
     9   *     notice, this list of conditions and the following disclaimer.
    10   *
    11   *   - Redistributions in binary form must reproduce the above copyright
    12   *     notice, this list of conditions and the following disclaimer in
    13   *     the documentation and/or other materials provided with the
    14   *     distribution.
    15   *
    16   *   - Neither the name of Pebble nor the names of its contributors may
    17   *     be used to endorse or promote products derived from this software
    18   *     without specific prior written permission.
    19   *
    20   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    21   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    22   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    23   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    24   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    25   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    26   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    27   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    28   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    29   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    30   * POSSIBILITY OF SUCH DAMAGE.
    31   */
    32  package net.sourceforge.pebble.confirmation;
    33  
         /* 
    P/P   *  Method: void net.sourceforge.pebble.confirmation.SimpleMathsConfirmationStrategy()
          */
    34  import javax.servlet.ServletRequest;
    35  import javax.servlet.http.HttpServletRequest;
    36  import java.util.Random;
    37  
    38  /**
    39   * Simple maths confirmation strategy that asks the user to add/subtract/multiply
    40   * two random numbers together.
    41   *
    42   * @author    Simon Brown
    43   */
    44  public class SimpleMathsConfirmationStrategy extends AbstractConfirmationStrategy {
    45  
    46    private static final String ARGUMENT1 = "SimpleMathsConfirmationStrategyArg1";
    47    private static final String ARGUMENT2 = "SimpleMathsConfirmationStrategyArg2";
    48    private static final String OPERATOR = "SimpleMathsConfirmationStrategyOperator";
    49    private static final String ANSWER = "SimpleMathsConfirmationStrategyAnswer";
    50  
    51    /**
    52     * Called before showing the confirmation page.
    53     *
    54     * @param request the HttpServletRequest used in the confirmation
    55     */
    56    public void setupConfirmation(HttpServletRequest request) {
             /* 
    P/P       *  Method: void setupConfirmation(HttpServletRequest)
              * 
              *  Preconditions:
              *    request != null
              * 
              *  Presumptions:
              *    (java.util.Random:nextInt(...)@58 + 1)*(java.util.Random:nextInt(...)@59 + 1) in -231..232-1
              *    java.util.Random:nextInt(...)@58 <= 232-2
              *    java.util.Random:nextInt(...)@58 + java.util.Random:nextInt(...)@59 in -231-2..232-3
              *    java.util.Random:nextInt(...)@59 <= 232-2
              *    java.util.Random:nextInt(...)@59 - java.util.Random:nextInt(...)@58 in -232+1..231
              *    ...
              * 
              *  Test Vectors:
              *    java.util.Random:nextInt(...)@60: {0}, {1}, {2}, {-231..-1, 3..232-1}
              */
    57      Random r = new Random();
    58      int arg1 = r.nextInt(10) + 1;
    59      int arg2 = r.nextInt(10) + 1;
    60      int op = r.nextInt(3);
    61      ((ServletRequest) request.getSession()).setAttribute(ARGUMENT1, arg1);
    62      ((ServletRequest) request.getSession()).setAttribute(ARGUMENT2, arg2);
    63  
    64      switch (op) {
    65        case 0 :
    66          ((ServletRequest) request.getSession()).setAttribute(OPERATOR, "+");
    67          ((ServletRequest) request.getSession()).setAttribute(ANSWER, arg1 + arg2);
    68          break;
    69        case 1 :
    70          ((ServletRequest) request.getSession()).setAttribute(OPERATOR, "-");
    71          ((ServletRequest) request.getSession()).setAttribute(ANSWER, arg1 - arg2);
    72          break;
    73        case 2 :
    74          ((ServletRequest) request.getSession()).setAttribute(OPERATOR, "*");
    75          ((ServletRequest) request.getSession()).setAttribute(ANSWER, arg1 * arg2);
    76          break;
    77      }
    78    }
    79  
    80    /**
    81     * Gets the URI of the confirmation page.
    82     *
    83     * @return a URI, relative to the web application root.
            /* 
    P/P      *  Method: String getUri()
             * 
             *  Postconditions:
             *    return_value == &".WEB-INF.jsp.confirmation.maths.jsp"
             */
    84     */
    85    public String getUri() {
    86      return "/WEB-INF/jsp/confirmation/maths.jsp";
    87    }
    88  
    89    /**
    90     * Called to determine whether confirmation was successful.
    91     *
    92     * @param request   the HttpServletRequest used in the confirmation
    93     * @return  true if the confirmation was successful, false otherwise
    94     */
    95    public boolean isConfirmed(HttpServletRequest request) {
             /* 
    P/P       *  Method: bool isConfirmed(HttpServletRequest)
              * 
              *  Preconditions:
              *    request != null
              * 
              *  Presumptions:
              *    javax.servlet.ServletRequest:getAttribute(...)@96 != null
              *    javax.servlet.http.HttpServletRequest:getSession(...)@96 != null
              * 
              *  Postconditions:
              *    init'ed(return_value)
              */
    96      Integer answer = (Integer)((ServletRequest) request.getSession()).getAttribute(ANSWER);
    97      String userAnswer = request.getParameter("answer");
    98  
    99      return answer.toString().equals(userAnswer);
   100    }
   101  
   102  }