Fix up compareTo method

zanata · Oct 15, 2013 · fe11078 · fe11078
1 parent 2f67456
commit fe11078
Showing 1 changed file with 11 additions and 2 deletions.
diff --git a/zanata-war/src/main/java/org/zanata/webtrans/shared/model/DocumentId.java b/zanata-war/src/main/java/org/zanata/webtrans/shared/model/DocumentId.java
@@ -59,7 +59,16 @@ public boolean equals(Object obj) {
 
     @Override
     public int compareTo(Object o) {
-        DocumentId compareTo = (DocumentId) o;
-        return this.getDocId().compareTo(compareTo.getDocId());
+        if (o == this) {
+            return 0;
+        }
+        if (o == null) {
+            return -1;
+        }
+        if (o instanceof DocumentId) {
+            DocumentId compareTo = (DocumentId) o;
+            return this.getDocId().compareTo(compareTo.getDocId());
+        }
+        return -1;
     }
 }