output: #fixed code
                                  @Test
      public void testSelectUpsertWithOldClient() throws Exception {
          // Insert data with new client and read with old client
          executeQueriesWithCurrentVersion(CREATE_ADD);
          executeQueryWithClientVersion(compatibleClientVersion, QUERY);
          assertExpectedOutput(CREATE_ADD, QUERY);
  
          // Insert more data with old client and read with new client
          executeQueryWithClientVersion(compatibleClientVersion, ADD_DATA);
          executeQueriesWithCurrentVersion(QUERY_MORE);
          assertExpectedOutput(ADD_DATA, QUERY_MORE);
      }
input: #vulnerable code 
                                  @Test
      public void testSelectUpsertWithOldClient() throws Exception {
          checkForPreConditions();
          // Insert data with new client and read with old client
          executeQueriesWithCurrentVersion(CREATE_ADD);
          executeQueryWithClientVersion(compatibleClientVersion, QUERY);
          assertTrue(compareOutput(CREATE_ADD, QUERY));
  
          // Insert more data with old client and read with new client
          executeQueryWithClientVersion(compatibleClientVersion, ADD_DATA);
          executeQueriesWithCurrentVersion(QUERY_MORE);
          assertTrue(compareOutput(ADD_DATA, QUERY_MORE));
      } 
                              #location 3 
                              #vulnerability type THREAD_SAFETY_VIOLATION