1 files changed, 4 insertions, 2 deletions
diff --git a/sonar-duplications/src/main/java/org/sonar/duplications/index/ClonePart.java b/sonar-duplications/src/main/java/org/sonar/duplications/index/ClonePart.java
index 630f52c1350..0130f167197 100644
--- a/sonar-duplications/src/main/java/org/sonar/duplications/index/ClonePart.java
+++ b/sonar-duplications/src/main/java/org/sonar/duplications/index/ClonePart.java
@@ -21,6 +21,8 @@ package org.sonar.duplications.index;
 
 import org.sonar.duplications.CodeFragment;
 
+import javax.annotation.Nullable;
+
 public class ClonePart implements CodeFragment {
 
   private final String resourceId;
@@ -63,8 +65,8 @@ public class ClonePart implements CodeFragment {
   }
 
   @Override
-  public boolean equals(Object obj) {
-    if (this.getClass() == obj.getClass()) {
+  public boolean equals(@Nullable Object obj) {
+    if (obj != null && this.getClass() == obj.getClass()) {
       ClonePart another = (ClonePart) obj;
       return another.resourceId.equals(resourceId)
         && another.startLine == startLine