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 * The contents of this file are subject to the terms of the Common Development

 * and Distribution License (the License). You may not use this file except in

 * compliance with the License.

 *

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 * or http://www.netbeans.org/cddl.txt.

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 * When distributing Covered Code, include this CDDL Header Notice in each file

 * and include the License file at http://www.netbeans.org/cddl.txt.

 * If applicable, add the following below the CDDL Header, with the fields

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 * "Portions Copyrighted [year] [name of copyright owner]"

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 * The Original Software is NetBeans. The Initial Developer of the Original

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 * Microsystems, Inc. All Rights Reserved.

 */

package org.netbeans.apifest.boolcircuit;

import java.security.CodeSource;

import java.security.Permission;

import java.security.PermissionCollection;

import java.security.Policy;

import java.util.Collection;

import java.util.Collections;

import java.util.Enumeration;

import junit.framework.TestCase;

import junit.framework.*;

/** This file contains the APIFest quest for day 2. Simply, turn the 

 * boolean circuit into circuit that can compute with double values from 0 to 1.

 * <p>

 * This means that where ever a boolean was used to represent input or 

 * output values, one can now use any double number from >= 0 and <= 1.

 * Still, to support backward compatibility, the operations with booleans

 * has to be kept available and have to work. In fact False shall be 

 * treated as 0 and True as 1.

 * <p>

 * The basic elements has to be modified to work on doubles in the following

 * way:

 * <ul>

 *   <li>negation - neg(x) = 1 - x, this is correct extension as neg(false)=neg(0)=1-0=1=true

 *   <li>and - and(x,y) = x * y, again this is fine as and(true,true)=1*1=true and also

 *             and(false,true)=0*1=0=false

 *   <li>or - or(x,y) = 1 - (1 - x) * (1 - y) and this is also ok as

 *             or(false,false) = 1 - (1 - 0) * (1 - 0) = 1 - 1 = 0 = false

 *             or(true,false) = 1 - (1 - 1) * (1 - 0) = 1 - 0 * 1 = 1 = true

 * </ul>

 * <p>

 * However as the circuits with doubles are more rich than plain boolean circuits,

 * there is additional requirement to allow any user of your API to write its 

 * own "element" type. This is all going to be exercise in the tests bellow

 * which you are supposed to implement.

 */

public class RealTest extends TestCase {

    static {

        // your code shall run without any permissions

    }

    public RealTest(String testName) {

        super(testName);

    }

    protected void setUp() throws Exception {

    }

    protected void tearDown() throws Exception {

    }

    /** First of all create a circuit which will evaluate

     * expression (X1 and X2) or not(x1). Hold the circuit

     * in some variable.

     *

     * Feed this circuit with x1=true, x2=false, assert result is false

     *

     * Feed the same circuit with x1=false, x2=true, assert result is true

     *

     * Feed the same circuit with x1=0.0, x2=1.0, assert result is 1.0

     *

     * Feed the same circuit with x1=0.5, x2=0.5, assert result is 0.625

     *

     * Feed the same circuit with x1=0.0, x2=2.0, make sure it throws an exception

     */

    public void testX1andX2orNotX1() {

        Circuit.Variable x1 = Circuit.var();

        Circuit.Variable x2 = Circuit.var();

        Circuit.Element el = Circuit.or(

            Circuit.and(x1, x2),

            Circuit.not(x1)

        );

        x1.assignValue(true); x2.assignValue(false);

        assertFalse(el.result());

        x1.assignValue(false); x2.assignValue(true);

        assertTrue(el.result());

        x1.assignValue(0.0); x2.assignValue(1.0);

        assertEquals(1.0, el.doubleResult());

        x1.assignValue(0.5); x2.assignValue(0.5);

        assertEquals(0.625, el.doubleResult());

        try {

            x1.assignValue(0.0); x2.assignValue(2.0);

            fail("Should throw an exception");

        } catch (IllegalArgumentException ex) {

            // ok

        }

    }

    /** Ensure that one variable cannot be filled with two different values.

     * Create a circuit for x1 and x1. Make sure that for any usage of your

     * API that would not lead to x1 * x1 result, an exception is thrown.

     * For example if there was a way to feed the circuit with two different 

     * values 0.3 and 0.5 an exception is thrown indicating that this is 

     * improper use of the circuit.

     */

    public void testImproperUseOfTheCircuit() {

        // no way to get 0.3 * 0.5 from the circuit

        Circuit.Variable x1 = Circuit.var();

        Circuit.Element el = Circuit.and(x1, x1);

        x1.assignValue(0.3);

        assertEquals(0.3 * 0.3, el.doubleResult());

        x1.assignValue(0.5);

        assertEquals(0.5 * 0.5, el.doubleResult());

    }

    /** Write your own element type called "gte" that will have two inputs and one output.

     * The output value will be 1 if x1 >= x2 and 0 otherwise. 

     * 

     * Create 

     * circuit for following expression: (x1 and not(x1)) gte x1

     *

     * Feed the circuit with 0.5 and verify the result is 0

     *

     * Feed the same circuit with 1 and verify the result is 0

     *

     * Feed the same circuit with 0 and verify the result is 1

     */

    public void testGreaterThanElement() {

        class GreaterThanEqual implements Circuit.Operation {

            public double computeResult(double... values) {

                return values[0] >= values[1] ? 1.0 : 0.0;

            }

        }

        Circuit.Variable x1 = Circuit.var();

        Circuit.Element gte = Circuit.operation(

            new GreaterThanEqual(), 

            Circuit.and(x1, Circuit.not(x1)),

            x1

        );

        x1.assignValue(0.5); assertEquals(0.0, gte.doubleResult());

        x1.assignValue(1.0); assertEquals(0.0, gte.doubleResult());

        x1.assignValue(0.0); assertEquals(1.0, gte.doubleResult());

    }

}