#vulnerable code 
                                @Test
    public void testUpsertDeleteWithOldClient() throws Exception {
        checkForPreConditions();
        // Insert data with old client and read with new client
        executeQueryWithClientVersion(compatibleClientVersion, CREATE_ADD);
        executeQueriesWithCurrentVersion(QUERY);
        assertTrue(compareOutput(CREATE_ADD, QUERY));

        // Deletes with the old client
        executeQueryWithClientVersion(compatibleClientVersion, ADD_DELETE);
        executeQueryWithClientVersion(compatibleClientVersion, QUERY_ADD_DELETE);
        assertTrue(compareOutput(ADD_DELETE, QUERY_ADD_DELETE));
    } 
                            #location 3 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                                @Test
    public void testUpsertDeleteWithOldClient() throws Exception {
        // Insert data with old client and read with new client
        executeQueryWithClientVersion(compatibleClientVersion, CREATE_ADD);
        executeQueriesWithCurrentVersion(QUERY);
        assertExpectedOutput(CREATE_ADD, QUERY);

        // Deletes with the old client
        executeQueryWithClientVersion(compatibleClientVersion, ADD_DELETE);
        executeQueryWithClientVersion(compatibleClientVersion, QUERY_ADD_DELETE);
        assertExpectedOutput(ADD_DELETE, QUERY_ADD_DELETE);
    }