1 /** 2 * Copyright (c) 2004-2011 QOS.ch 3 * All rights reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining 6 * a copy of this software and associated documentation files (the 7 * "Software"), to deal in the Software without restriction, including 8 * without limitation the rights to use, copy, modify, merge, publish, 9 * distribute, sublicense, and/or sell copies of the Software, and to 10 * permit persons to whom the Software is furnished to do so, subject to 11 * the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be 14 * included in all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 17 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 20 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 21 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 22 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 23 * 24 */ 25 package org.slf4j.profiler; 26 27 import java.util.ArrayList; 28 import java.util.Arrays; 29 30 public class SortAndPruneComposites { 31 32 static String NESTED_PROFILER_NAME = "SORT_AND_PRUNE"; 33 34 final int[] originalArray; 35 final int originalArrrayLength; 36 SortAndPruneComposites(int[] randomArray)37 public SortAndPruneComposites(int[] randomArray) { 38 this.originalArray = randomArray; 39 this.originalArrrayLength = randomArray.length; 40 41 } 42 sortAndPruneComposites()43 public int[] sortAndPruneComposites() { 44 // retrieve previously registered profiler named "SORT_AND_PRUNE" 45 ProfilerRegistry profilerRegistry = ProfilerRegistry.getThreadContextInstance(); 46 Profiler sortProfiler = profilerRegistry.get(NESTED_PROFILER_NAME); 47 48 // start a new stopwatch called SORT 49 sortProfiler.start("SORT"); 50 int[] sortedArray = sort(); 51 // start a new stopwatch called PRUNE_COMPOSITES 52 sortProfiler.start("PRUNE_COMPOSITES"); 53 int result[] = pruneComposites(sortedArray); 54 55 return result; 56 } 57 sort()58 private int[] sort() { 59 int[] sortedArray = new int[originalArrrayLength]; 60 System.arraycopy(originalArray, 0, sortedArray, 0, originalArrrayLength); 61 Arrays.sort(sortedArray); 62 return sortedArray; 63 } 64 pruneComposites(int[] sortedArray)65 int[] pruneComposites(int[] sortedArray) { 66 ArrayList<Integer> primesArray = new ArrayList<Integer>(); 67 for (int i = 0; i < originalArrrayLength; i++) { 68 int n = sortedArray[i]; 69 if (isPrime(n)) { 70 primesArray.add(n); 71 } 72 } 73 int resultSize = primesArray.size(); 74 int[] result = new int[resultSize]; 75 76 for (int i = 0; i < resultSize; i++) { 77 result[i] = primesArray.get(i); 78 } 79 return result; 80 } 81 isPrime(int n)82 public boolean isPrime(int n) { 83 if (n < 2) { 84 return false; 85 } 86 if (n % 2 == 0) { 87 return false; 88 } 89 for (int i = 3; i * i <= n; i += 2) { 90 if (n % i == 0) { 91 return false; 92 } 93 } 94 return true; 95 } 96 } 97