SONAR-5672 Don't save DSM when there is no dependency or more than 200 components

6 files changed, 50 insertions, 32 deletions

diff --git a/sonar-graph/src/main/java/org/sonar/graph/DirectedGraph.java b/sonar-graph/src/main/java/org/sonar/graph/DirectedGraph.java
index ecbb0fb6d72..c0d63887b89 100644
--- a/sonar-graph/src/main/java/org/sonar/graph/DirectedGraph.java
+++ b/sonar-graph/src/main/java/org/sonar/graph/DirectedGraph.java
@@ -22,7 +22,7 @@ package org.sonar.graph;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
-import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -32,7 +32,7 @@ public class DirectedGraph<V, E extends Edge<V>> implements DirectedGraphAccesso
   private EdgeFactory<V, E> edgeFactory;
   private Map<V, Map<V, E>> outgoingEdgesByVertex = new HashMap<V, Map<V, E>>();
   private Map<V, Map<V, E>> incomingEdgesByVertex = new HashMap<V, Map<V, E>>();
-  private Set<V> vertices = new HashSet<V>();
+  private Set<V> vertices = new LinkedHashSet<V>();
 
   public DirectedGraph() {
   }
@@ -60,7 +60,7 @@ public class DirectedGraph<V, E extends Edge<V>> implements DirectedGraphAccesso
   private void checkEdgeFacory() {
     if (edgeFactory == null) {
       throw new IllegalStateException(
-          "EdgeFactory<V, E> has not been defined. Please use the 'public E addEdge(V from, V to, E edge)' method.");
+        "EdgeFactory<V, E> has not been defined. Please use the 'public E addEdge(V from, V to, E edge)' method.");
     }
   }
 
@@ -133,7 +133,7 @@ public class DirectedGraph<V, E extends Edge<V>> implements DirectedGraphAccesso
   public Collection<E> getOutgoingEdges(V from) {
     Map<V, E> outgoingEdges = outgoingEdgesByVertex.get(from);
     if (outgoingEdges == null) {
-      return new HashSet<E>();
+      return new LinkedHashSet<E>();
     }
     return outgoingEdges.values();
   }
@@ -142,7 +142,7 @@ public class DirectedGraph<V, E extends Edge<V>> implements DirectedGraphAccesso
   public Collection<E> getIncomingEdges(V to) {
     Map<V, E> incomingEdges = incomingEdgesByVertex.get(to);
     if (incomingEdges == null) {
-      return new HashSet<E>();
+      return new LinkedHashSet<E>();
     }
     return incomingEdges.values();
   }
diff --git a/sonar-graph/src/main/java/org/sonar/graph/Dsm.java b/sonar-graph/src/main/java/org/sonar/graph/Dsm.java
index fc9f386fff2..69e85c251da 100644
--- a/sonar-graph/src/main/java/org/sonar/graph/Dsm.java
+++ b/sonar-graph/src/main/java/org/sonar/graph/Dsm.java
@@ -27,17 +27,17 @@ import java.util.Set;
 
 public class Dsm<V> {
 
-  private V[] vertices;
-  private DsmCell[][] cells;
-  private int dimension;
-  private DirectedGraphAccessor<V, ? extends Edge<V>> graph;
+  private final V[] vertices;
+  private final DsmCell[][] cells;
+  private final int dimension;
+  private final DirectedGraphAccessor<V, ? extends Edge<V>> graph;
+  private boolean atLeastOneDependency = false;
 
   public Dsm(DirectedGraphAccessor<V, ? extends Edge<V>> graph, Collection<V> vertices, Set<Edge> feedbackEdges) {
     this.graph = graph;
     this.dimension = vertices.size();
-    this.cells = new DsmCell[dimension][dimension];
-    initVertices(vertices);
-    initCells(feedbackEdges);
+    this.vertices = initVertices(vertices);
+    this.cells = initCells(feedbackEdges);
   }
 
   public Dsm(DirectedGraphAccessor<V, ? extends Edge<V>> acyclicGraph, Set<Edge> feedbackEdges) {
@@ -48,7 +48,8 @@ public class Dsm<V> {
     this(acyclicGraph, acyclicGraph.getVertices(), Collections.<Edge>emptySet());
   }
 
-  private void initCells(Set<Edge> feedbackEdges) {
+  private DsmCell[][] initCells(Set<Edge> feedbackEdges) {
+    DsmCell[][] cells = new DsmCell[dimension][dimension];
     for (int x = 0; x < dimension; x++) {
       for (int y = 0; y < dimension; y++) {
         V from = vertices[x];
@@ -56,20 +57,23 @@ public class Dsm<V> {
 
         Edge<V> edge = graph.getEdge(from, to);
         if (edge != null) {
+          atLeastOneDependency = true;
           boolean isFeedbackEdge = feedbackEdges.contains(edge);
           cells[x][y] = new DsmCell(edge, isFeedbackEdge);
         }
       }
     }
+    return cells;
   }
 
-  private void initVertices(Collection<V> verticesCol) {
-    this.vertices = (V[]) new Object[dimension];
+  private V[] initVertices(Collection<V> verticesCol) {
+    V[] vertices = (V[]) new Object[dimension];
     int i = 0;
     for (V vertex : verticesCol) {
       vertices[i] = vertex;
       i++;
     }
+    return vertices;
   }
 
   public V getVertex(int rowIndex) {
@@ -159,11 +163,21 @@ public class Dsm<V> {
     return cell != null ? cell : new DsmCell(null, false);
   }
 
+  /**
+   * @since 5.0
+   */
   @CheckForNull
   public DsmCell cell(int x, int y) {
     return cells[x][y];
   }
 
+  /**
+   * @since 5.0
+   */
+  public boolean hasAtLeastOneDependency() {
+    return atLeastOneDependency;
+  }
+
   public V[] getVertices() {
     V[] verticesCopy = (V[]) new Object[vertices.length];
     System.arraycopy(vertices, 0, verticesCopy, 0, vertices.length);
diff --git a/sonar-graph/src/main/java/org/sonar/graph/DsmScanner.java b/sonar-graph/src/main/java/org/sonar/graph/DsmScanner.java
index 4057748c2c6..beb5318f74b 100644
--- a/sonar-graph/src/main/java/org/sonar/graph/DsmScanner.java
+++ b/sonar-graph/src/main/java/org/sonar/graph/DsmScanner.java
@@ -26,7 +26,7 @@ import java.io.LineNumberReader;
 import java.io.Reader;
 import java.io.StringReader;
 import java.util.Arrays;
-import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.Set;
 
 public final class DsmScanner {
@@ -36,7 +36,7 @@ public final class DsmScanner {
   private static final char FEEDBACK_EDGE_FLAG = '*';
   private final DirectedGraph<String, StringEdge> graph = DirectedGraph.createStringDirectedGraph();
   private String[] vertices;
-  private Set<Edge> feedbackEdges = new HashSet<Edge>();
+  private Set<Edge> feedbackEdges = new LinkedHashSet<Edge>();
 
   private DsmScanner(Reader reader) {
     this.reader = new LineNumberReader(reader);
@@ -49,7 +49,7 @@ public final class DsmScanner {
         readRow(i);
       }
     } catch (IOException e) {
-      throw new RuntimeException("Unable to read DSM content.", e); //NOSONAR
+      throw new RuntimeException("Unable to read DSM content.", e); // NOSONAR
     }
     Dsm<String> dsm = new Dsm<String>(graph, graph.getVertices(), feedbackEdges);
     DsmManualSorter.sort(dsm, Arrays.asList(vertices));
diff --git a/sonar-graph/src/main/java/org/sonar/graph/FeedbackCycle.java b/sonar-graph/src/main/java/org/sonar/graph/FeedbackCycle.java
index 81de9669e43..7a22fcd0c0d 100644
--- a/sonar-graph/src/main/java/org/sonar/graph/FeedbackCycle.java
+++ b/sonar-graph/src/main/java/org/sonar/graph/FeedbackCycle.java
@@ -20,15 +20,15 @@
 
 package org.sonar.graph;
 
+import com.google.common.collect.LinkedHashMultiset;
+import com.google.common.collect.Multiset;
+
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Set;
 
-import com.google.common.collect.HashMultiset;
-import com.google.common.collect.Multiset;
-
 /**
  * Note: this class has a natural ordering that is inconsistent with equals
  */
@@ -70,7 +70,7 @@ public final class FeedbackCycle implements Iterable<FeedbackEdge>, Comparable<F
   }
 
   private static Multiset<Edge> createBagWithAllEdgesOfCycles(Set<Cycle> cycles) {
-    Multiset<Edge> edgesBag = HashMultiset.create();
+    Multiset<Edge> edgesBag = LinkedHashMultiset.create();
     for (Cycle cycle : cycles) {
       for (Edge edge : cycle.getEdges()) {
         edgesBag.add(edge);
@@ -94,7 +94,9 @@ public final class FeedbackCycle implements Iterable<FeedbackEdge>, Comparable<F
 
   @Override
   public int compareTo(FeedbackCycle feedbackCycle) {
-    if (getTotalOccurrencesOfEdgesInCycle() < feedbackCycle.getTotalOccurrencesOfEdgesInCycle()) {//NOSONAR this class has a natural ordering that is inconsistent with equals
+    if (getTotalOccurrencesOfEdgesInCycle() < feedbackCycle.getTotalOccurrencesOfEdgesInCycle()) {// NOSONAR this class has a natural
+                                                                                                  // ordering that is inconsistent with
+                                                                                                  // equals
       return -1;
     }
     if (getTotalOccurrencesOfEdgesInCycle() == feedbackCycle.getTotalOccurrencesOfEdgesInCycle()) {
diff --git a/sonar-graph/src/main/java/org/sonar/graph/IncrementalCyclesAndFESSolver.java b/sonar-graph/src/main/java/org/sonar/graph/IncrementalCyclesAndFESSolver.java
index 576f461e4c1..cd814c615f4 100644
--- a/sonar-graph/src/main/java/org/sonar/graph/IncrementalCyclesAndFESSolver.java
+++ b/sonar-graph/src/main/java/org/sonar/graph/IncrementalCyclesAndFESSolver.java
@@ -20,12 +20,12 @@
 package org.sonar.graph;
 
 import java.util.Collection;
-import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.Set;
 
 public class IncrementalCyclesAndFESSolver<V> {
 
-  private Set<Cycle> cycles = new HashSet<Cycle>();
+  private Set<Cycle> cycles = new LinkedHashSet<Cycle>();
   private long searchCyclesCalls = 0;
   private static final int DEFAULT_MAX_SEARCH_DEPTH_AT_FIRST = 3;
   private static final int DEFAULT_MAX_CYCLES_TO_FOUND_BY_ITERATION = 100;
@@ -37,7 +37,7 @@ public class IncrementalCyclesAndFESSolver<V> {
   }
 
   public IncrementalCyclesAndFESSolver(DirectedGraphAccessor<V, ? extends Edge> graph, Collection<V> vertices, int maxSearchDepthAtFirst,
-      int maxCyclesToFoundByIteration) {
+    int maxCyclesToFoundByIteration) {
 
     iterations++;
     CycleDetector<V> cycleDetector = new CycleDetector<V>(graph, vertices);
diff --git a/sonar-graph/src/main/java/org/sonar/graph/MinimumFeedbackEdgeSetSolver.java b/sonar-graph/src/main/java/org/sonar/graph/MinimumFeedbackEdgeSetSolver.java
index 39a5c374b9f..aaebdced22c 100644
--- a/sonar-graph/src/main/java/org/sonar/graph/MinimumFeedbackEdgeSetSolver.java
+++ b/sonar-graph/src/main/java/org/sonar/graph/MinimumFeedbackEdgeSetSolver.java
@@ -19,7 +19,9 @@
  */
 package org.sonar.graph;
 
-import java.util.*;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
 
 public class MinimumFeedbackEdgeSetSolver {
 
@@ -62,7 +64,7 @@ public class MinimumFeedbackEdgeSetSolver {
    * Get edges tagged as feedback.
    */
   public Set<Edge> getEdges() {
-    Set<Edge> edges = new HashSet<Edge>();
+    Set<Edge> edges = new LinkedHashSet<Edge>();
     for (FeedbackEdge fe : feedbackEdges) {
       edges.add(fe.getEdge());
     }
@@ -70,7 +72,7 @@ public class MinimumFeedbackEdgeSetSolver {
   }
 
   private void run() {
-    Set<FeedbackEdge> pendingFeedbackEdges = new HashSet<FeedbackEdge>();
+    Set<FeedbackEdge> pendingFeedbackEdges = new LinkedHashSet<FeedbackEdge>();
     if (cyclesNumber < maxNumberCyclesForSearchingMinimumFeedback) {
       searchFeedbackEdges(0, 0, pendingFeedbackEdges);
     } else {
@@ -79,7 +81,7 @@ public class MinimumFeedbackEdgeSetSolver {
   }
 
   private void lightResearchForFeedbackEdges() {
-    feedbackEdges = new HashSet<FeedbackEdge>();
+    feedbackEdges = new LinkedHashSet<FeedbackEdge>();
     for (FeedbackCycle cycle : feedbackCycles) {
       for (FeedbackEdge edge : cycle) {
         feedbackEdges.add(edge);
@@ -87,7 +89,7 @@ public class MinimumFeedbackEdgeSetSolver {
       }
     }
     minimumFeedbackEdgesWeight = 0;
-    for(FeedbackEdge edge : feedbackEdges) {
+    for (FeedbackEdge edge : feedbackEdges) {
       minimumFeedbackEdgesWeight += edge.getWeight();
     }
   }
@@ -103,7 +105,7 @@ public class MinimumFeedbackEdgeSetSolver {
 
     if (level == cyclesNumber) {
       minimumFeedbackEdgesWeight = pendingWeight;
-      feedbackEdges = new HashSet<FeedbackEdge>(pendingFeedbackEdges);
+      feedbackEdges = new LinkedHashSet<FeedbackEdge>(pendingFeedbackEdges);
       return;
     }