001 /* 002 * Sonar, open source software quality management tool. 003 * Copyright (C) 2009 SonarSource SA 004 * mailto:contact AT sonarsource DOT com 005 * 006 * Sonar is free software; you can redistribute it and/or 007 * modify it under the terms of the GNU Lesser General Public 008 * License as published by the Free Software Foundation; either 009 * version 3 of the License, or (at your option) any later version. 010 * 011 * Sonar is distributed in the hope that it will be useful, 012 * but WITHOUT ANY WARRANTY; without even the implied warranty of 013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014 * Lesser General Public License for more details. 015 * 016 * You should have received a copy of the GNU Lesser General Public 017 * License along with Sonar; if not, write to the Free Software 018 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02 019 */ 020 package org.sonar.squid.graph; 021 022 import java.util.ArrayList; 023 import java.util.Arrays; 024 import java.util.Collection; 025 import java.util.List; 026 027 public class CycleDetector { 028 029 private final Collection<? extends Node> resourcesToAnalyze; 030 private final List<Node> alreadyAnalyzed; 031 private final List<Cycle> cycles = new ArrayList<Cycle>(); ; 032 033 public CycleDetector(Collection<? extends Node> resourcesToAnalyze) { 034 this.resourcesToAnalyze = resourcesToAnalyze; 035 this.alreadyAnalyzed = new ArrayList<Node>(); 036 analyze(); 037 } 038 039 public CycleDetector(Node... resources) { 040 this(Arrays.asList(resources)); 041 } 042 043 private void analyze() { 044 for (Node resource : resourcesToAnalyze) { 045 if (! alreadyAnalyzed.contains(resource)) { 046 analyze(resource, new ArrayList<Node>()); 047 } 048 } 049 } 050 051 private void analyze(Node node, List<Node> path) { 052 path.add(node); 053 alreadyAnalyzed.add(node); 054 for (Node dependency : node.dependsUpon()) { 055 if (path.contains(dependency)) { 056 Cycle cycle = new Cycle(new ArrayList<Node>(path.subList(path.indexOf(dependency), path.indexOf(node) + 1))); 057 if (!cycles.contains(cycle)) { 058 cycles.add(cycle); 059 } 060 } else { 061 analyze(dependency, new ArrayList<Node>(path)); 062 } 063 } 064 } 065 066 public List<Cycle> getCycles() { 067 return cycles; 068 } 069 070 public Cycle getCycles(int cycleNumber) { 071 return cycles.get(cycleNumber); 072 } 073 074 public int getCyclesNumber() { 075 return cycles.size(); 076 } 077 078 @Override 079 public String toString() { 080 StringBuilder builder = new StringBuilder(); 081 builder.append("There are " + getCyclesNumber() + " cycles.\n"); 082 for (Cycle cycle : cycles) { 083 builder.append(cycle); 084 } 085 return builder.toString(); 086 } 087 088 public boolean contains(Cycle cycle) { 089 return cycles.contains(cycle); 090 } 091 }