add ut

kyuubi-server/src/main/scala/yaooqinn/kyuubi/cli/Handle.scala

@@ -44,7 +44,7 @@ abstract class Handle(val handleId: HandleIdentifier) {
       if (other.handleId != null) {
         return false
       }
-    } else if (!(handleId == other.handleId)) {
+    } else if (handleId != other.handleId) {
       return false
     }
 

kyuubi-server/src/test/scala/yaooqinn/kyuubi/cli/HandleSuite.scala

@@ -27,6 +27,14 @@ class HandleSuite extends SparkFunSuite {
     val handle3 = TestHandle3(handle2.handleId.toTHandleIdentifier)
     assert(handle1 === handle2)
     assert(handle1 === handle3)
+    val handle4 = TestHandle2(null)
+    assert(handle4.hashCode === 31)
+    assert(!handle4.equals(null))
+    assert(!handle4.equals(new Object))
+    assert(!handle2.equals(handle4))
+    assert(handle4.equals(handle4))
+    assert(!handle4.equals(handle2))
+    assert(handle2.equals(handle2))
   }
 
 }