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/*
* The MIT License (MIT)
*
* Copyright (c) 2015 Camil Staps <info@camilstaps.nl>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package com.camilstaps.die;
import org.junit.After;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import static org.junit.Assert.*;
/**
*
* @author camilstaps
*/
public class DieTest {
private static final int PLAYERS = 100;
private static final int THROWS = 100;
private static final double ACCEPTABLE_LOWER_BOUND = 0.95;
private static final double ACCEPTABLE_UPPER_BOUND = 1.05;
public DieTest() {
}
@BeforeClass
public static void setUpClass() {
}
@AfterClass
public static void tearDownClass() {
}
@Before
public void setUp() {
}
@After
public void tearDown() {
}
/**
* Test that the probabilities for every different possible outcome are more or less close to the expected probability
* Accuracy of this test depends on PLAYERS, THROWS, ACCEPTABLE_LOWER_BOUND and ACCEPTABLE_UPPER_BOUND
*
* With non-thread safe solutions, this test most of the time fails. With thread-safe solutions, the test normally passes.
*/
@Test
public void correctProbabilities() {
// Start players
Die die = new Die();
Player players[] = new Player[PLAYERS];
Thread threads[] = new Thread[PLAYERS];
for (int i = 0; i < PLAYERS; i++) {
players[i] = new Player("Player " + i, die, THROWS);
threads[i] = new Thread(players[i]);
threads[i].start();
}
// Gather data
int pips_counts[] = new int[Die.MAX_PIPS];
for (int i = 0; i < PLAYERS; i++) {
try {
threads[i].join();
for (int p : players[i].getPipss()) {
pips_counts[p - 1]++;
}
} catch (InterruptedException e) {
System.err.println(e);
}
}
// Verification
int lower_bound = (int) (PLAYERS * THROWS / Die.MAX_PIPS * ACCEPTABLE_LOWER_BOUND);
int upper_bound = (int) (PLAYERS * THROWS / Die.MAX_PIPS * ACCEPTABLE_UPPER_BOUND);
System.out.println("Normal: " + PLAYERS * THROWS / Die.MAX_PIPS);
System.out.println("Lower bound: " + lower_bound + " (" + ACCEPTABLE_LOWER_BOUND + ")");
System.out.println("Upper bound: " + upper_bound + " (" + ACCEPTABLE_UPPER_BOUND + ")");
for (int i = 0; i < Die.MAX_PIPS; i++) {
System.out.println("Number of " + i + ": " + pips_counts[i]);
assertTrue("Number of " + i + " out of range", pips_counts[i] > lower_bound && pips_counts[i] < upper_bound);
}
}
}
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