From c78f13b422d5f8ea61bda50a270d557b0dfceb95 Mon Sep 17 00:00:00 2001 From: Camil Staps Date: Tue, 19 May 2015 23:25:28 +0200 Subject: Week13 die --- Week13 Die/test/com/camilstaps/die/DieTest.java | 106 ++++++++++++++++++++++++ 1 file changed, 106 insertions(+) create mode 100644 Week13 Die/test/com/camilstaps/die/DieTest.java (limited to 'Week13 Die/test/com/camilstaps/die/DieTest.java') diff --git a/Week13 Die/test/com/camilstaps/die/DieTest.java b/Week13 Die/test/com/camilstaps/die/DieTest.java new file mode 100644 index 0000000..2f1556e --- /dev/null +++ b/Week13 Die/test/com/camilstaps/die/DieTest.java @@ -0,0 +1,106 @@ +/* + * The MIT License (MIT) + * + * Copyright (c) 2015 Camil Staps + * + * 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); + } + } +} -- cgit v1.2.3