4 files changed, 27 insertions, 1 deletions
diff --git a/sonar-duplications/src/main/java/org/sonar/duplications/index/CloneIndex.java b/sonar-duplications/src/main/java/org/sonar/duplications/index/CloneIndex.java
index e529a600f54..11cdc7e680f 100644
--- a/sonar-duplications/src/main/java/org/sonar/duplications/index/CloneIndex.java
+++ b/sonar-duplications/src/main/java/org/sonar/duplications/index/CloneIndex.java
@@ -52,4 +52,6 @@ public interface CloneIndex {
    */
   Iterator<ResourceBlocks> iterator();
 
+  
+  int noResources();
 }
diff --git a/sonar-duplications/src/main/java/org/sonar/duplications/index/MemoryCloneIndex.java b/sonar-duplications/src/main/java/org/sonar/duplications/index/MemoryCloneIndex.java
index 0acb4edc0bb..bbfff14680f 100644
--- a/sonar-duplications/src/main/java/org/sonar/duplications/index/MemoryCloneIndex.java
+++ b/sonar-duplications/src/main/java/org/sonar/duplications/index/MemoryCloneIndex.java
@@ -54,4 +54,9 @@ public class MemoryCloneIndex implements CloneIndex {
     throw new UnsupportedOperationException();
   }
 
+  @Override
+  public int noResources() {
+    return byResource.keySet().size();
+  }
+
 }
diff --git a/sonar-duplications/src/main/java/org/sonar/duplications/index/PackedMemoryCloneIndex.java b/sonar-duplications/src/main/java/org/sonar/duplications/index/PackedMemoryCloneIndex.java
index a0e43ffab6f..97a97d792c4 100644
--- a/sonar-duplications/src/main/java/org/sonar/duplications/index/PackedMemoryCloneIndex.java
+++ b/sonar-duplications/src/main/java/org/sonar/duplications/index/PackedMemoryCloneIndex.java
@@ -120,7 +120,7 @@ public class PackedMemoryCloneIndex extends AbstractCloneIndex {
   private Block createBlock(int index, String resourceId, @Nullable ByteArray byteHash) {
     int offset = index * blockInts;
     ByteArray blockHash;
-    
+
     if (byteHash == null) {
       int[] hash = new int[hashInts];
       for (int j = 0; j < hashInts; j++) {
@@ -371,4 +371,22 @@ public class PackedMemoryCloneIndex extends AbstractCloneIndex {
     }
   };
 
+  @Override
+  /**
+   * Computation is O(N)
+   */
+  public int noResources() {
+    ensureSorted();
+    int count = 0;
+    String lastResource = null;
+
+    for (int i = 0; i < size; i++) {
+      String resource = resourceIds[resourceIdsIndex[i]];
+      if (resource != null && !resource.equals(lastResource)) {
+        count++;
+        lastResource = resource;
+      }
+    }
+    return count;
+  }
 }
diff --git a/sonar-duplications/src/test/java/org/sonar/duplications/index/PackedMemoryCloneIndexTest.java b/sonar-duplications/src/test/java/org/sonar/duplications/index/PackedMemoryCloneIndexTest.java
index d96f6ebeaf9..09ff7f055cc 100644
--- a/sonar-duplications/src/test/java/org/sonar/duplications/index/PackedMemoryCloneIndexTest.java
+++ b/sonar-duplications/src/test/java/org/sonar/duplications/index/PackedMemoryCloneIndexTest.java
@@ -54,6 +54,7 @@ public class PackedMemoryCloneIndexTest {
     index.insert(newBlock("e", 2));
     index.insert(newBlock("e", 3));
 
+    assertThat(index.noResources()).isEqualTo(5);
     assertThat(index.getBySequenceHash(new ByteArray(1L)).size(), is(5));
     assertThat(index.getBySequenceHash(new ByteArray(2L)).size(), is(2));
     assertThat(index.getBySequenceHash(new ByteArray(3L)).size(), is(1));