samples/apifest1/day2/stackbasedsolution/test/org/netbeans/apifest/boolcircuit/RealTest.java
author Jaroslav Tulach <jtulach@netbeans.org>
Sat, 14 Jun 2008 09:52:45 +0200
changeset 52 4257f4cf226b
permissions -rw-r--r--
Adding samples from API fest to the repository, including pieces of their code in the document, not just links
     1 /*
     2  * The contents of this file are subject to the terms of the Common Development
     3  * and Distribution License (the License). You may not use this file except in
     4  * compliance with the License.
     5  *
     6  * You can obtain a copy of the License at http://www.netbeans.org/cddl.html
     7  * or http://www.netbeans.org/cddl.txt.
     8  *
     9  * When distributing Covered Code, include this CDDL Header Notice in each file
    10  * and include the License file at http://www.netbeans.org/cddl.txt.
    11  * If applicable, add the following below the CDDL Header, with the fields
    12  * enclosed by brackets [] replaced by your own identifying information:
    13  * "Portions Copyrighted [year] [name of copyright owner]"
    14  *
    15  * The Original Software is NetBeans. The Initial Developer of the Original
    16  * Software is Sun Microsystems, Inc. Portions Copyright 1997-2006 Sun
    17  * Microsystems, Inc. All Rights Reserved.
    18  */
    19 
    20 package org.netbeans.apifest.boolcircuit;
    21 
    22 import java.security.CodeSource;
    23 import java.security.Permission;
    24 import java.security.PermissionCollection;
    25 import java.security.Policy;
    26 import java.util.Arrays;
    27 import java.util.Collection;
    28 import java.util.Collections;
    29 import java.util.Enumeration;
    30 import java.util.Stack;
    31 import junit.framework.TestCase;
    32 import junit.framework.*;
    33 
    34 /** This file contains the APIFest quest for day 2. Simply, turn the 
    35  * boolean circuit into circuit that can compute with double values from 0 to 1.
    36  * <p>
    37  * This means that where ever a boolean was used to represent input or 
    38  * output values, one can now use any double number from >= 0 and <= 1.
    39  * Still, to support backward compatibility, the operations with booleans
    40  * has to be kept available and have to work. In fact False shall be 
    41  * treated as 0 and True as 1.
    42  * <p>
    43  * The basic elements has to be modified to work on doubles in the following
    44  * way:
    45  * <ul>
    46  *   <li>negation - neg(x) = 1 - x, this is correct extension as neg(false)=neg(0)=1-0=1=true
    47  *   <li>and - and(x,y) = x * y, again this is fine as and(true,true)=1*1=true and also
    48  *             and(false,true)=0*1=0=false
    49  *   <li>or - or(x,y) = 1 - (1 - x) * (1 - y) and this is also ok as
    50  *             or(false,false) = 1 - (1 - 0) * (1 - 0) = 1 - 1 = 0 = false
    51  *             or(true,false) = 1 - (1 - 1) * (1 - 0) = 1 - 0 * 1 = 1 = true
    52  * </ul>
    53  * <p>
    54  * However as the circuits with doubles are more rich than plain boolean circuits,
    55  * there is additional requirement to allow any user of your API to write its 
    56  * own "element" type. This is all going to be exercise in the tests bellow
    57  * which you are supposed to implement.
    58  */
    59 public class RealTest extends TestCase {
    60     static {
    61         // your code shall run without any permissions
    62     }
    63     
    64     public RealTest(String testName) {
    65         super(testName);
    66     }
    67 
    68     protected void setUp() throws Exception {
    69     }
    70 
    71     protected void tearDown() throws Exception {
    72     }
    73     
    74     
    75     /** First of all create a circuit which will evaluate
    76      * expression (X1 and X2) or not(x1). Hold the circuit
    77      * in some variable.
    78      *
    79      * Feed this circuit with x1=true, x2=false, assert result is false
    80      *
    81      * Feed the same circuit with x1=false, x2=true, assert result is true
    82      *
    83      * Feed the same circuit with x1=0.0, x2=1.0, assert result is 1.0
    84      *
    85      * Feed the same circuit with x1=0.5, x2=0.5, assert result is 0.625
    86      *
    87      * Feed the same circuit with x1=0.0, x2=2.0, make sure it throws an exception
    88      */
    89     public void testX1andX2orNotX1() {
    90         Circuit2 trivX1 = CircuitFactory.getTrivialCircuit(0);
    91         Circuit2 trivX2 = CircuitFactory.getTrivialCircuit(1);
    92         Circuit2 cAnd = CircuitFactory.join(trivX1, trivX2, Operation.AND);
    93         Circuit2 cNeg = CircuitFactory.join(trivX1, trivX2, Operation.NEG);
    94         Circuit2 cOr = CircuitFactory.join(CircuitFactory.getBasicCircuit (Operation.AND), CircuitFactory.getBasicCircuit(Operation.NEG), Operation.OR);
    95 
    96         Stack<Character> s = new Stack<Character> ();
    97         s.addAll(Arrays.asList('1', '1', '0', '1'));
    98         
    99         assertEquals ("Feed this circuit with x1=true, x2=false, assert result is false", '0', cOr.evaluate(s));        
   100         assertEquals ("Feed the same circuit with x1=0.0, x2=1.0, assert result is 1.0", 1.0, cOr.evaluate(0.0,1.0));
   101         assertEquals ("Feed the same circuit with x1=0.5, x2=0.5, assert result is 0.625", 0.625, cOr.evaluate(0.5,0.5));
   102         try {
   103             assertEquals ("Feed the same circuit with x1=0.0, x2=2.0, make sure it throws an exception", 0, cOr.evaluate(0.0,2.0));
   104             fail ("Feed the same circuit with x1=0.0, x2=2.0, make sure it throws an exception");
   105         } catch (Exception x) {
   106         }
   107     }
   108     
   109     /** Ensure that one variable cannot be filled with two different values.
   110      * Create a circuit for x1 and x1. Make sure that for any usage of your
   111      * API that would not lead to x1 * x1 result, an exception is thrown.
   112      * For example if there was a way to feed the circuit with two different 
   113      * values 0.3 and 0.5 an exception is thrown indicating that this is 
   114      * improper use of the circuit.
   115      */
   116     public void testImproperUseOfTheCircuit() {
   117         Circuit2 trivX1 = CircuitFactory.getTrivialCircuit(0);
   118         assertEquals ("0.25", 0.25, CircuitFactory.join(trivX1, trivX1, Operation.AND).evaluate(0.5, 2));
   119     }
   120     
   121     /** Write your own element type called "gte" that will have two inputs and one output.
   122      * The output value will be 1 if x1 >= x2 and 0 otherwise. 
   123      * 
   124      * Create 
   125      * circuit for following expression: (x1 and not(x1)) gte x1
   126      *
   127      * Feed the circuit with 0.5 and verify the result is 0
   128      *
   129      * Feed the same circuit with 1 and verify the result is 0
   130      *
   131      * Feed the same circuit with 0 and verify the result is 1
   132      */
   133     public void testGreaterThanEqualElement() {
   134 //        fail("task3");
   135         Operation gte = new Operation () {
   136 
   137             public char evaluate(char i1, char i2) throws IllegalArgumentException {
   138                 assert false : "Not supported";
   139                 return 'x';
   140             }
   141 
   142             public double evaluate(double i1, double i2) throws IllegalArgumentException {
   143                 if (i1 < 0 || i1 > 1) {
   144                     throw new IllegalArgumentException ("Invalid input parameter: " + i1);
   145                 }
   146                 if (i2 < 0 || i2 > 1) {
   147                     throw new IllegalArgumentException ("Invalid input parameter: " + i2);
   148                 }
   149                 return i1 >= i2 ? 1 : 0;
   150             }
   151         };
   152     }
   153 }