@Test
public void testClientNull() throws IOException {

    String tableName = "testTable";
    // Mock getting client failed (returns null)
    when(dynamoDBClientFetcher.getDynamoDBClient(any(), any())).thenReturn(null);
    DynamoDBStatusCheckerTestClass dynamoDBStatusChecker = new DynamoDBStatusCheckerTestClass(tableName);
    try {
        dynamoDBStatusChecker.check();
        fail();
    } catch (StatusCheckException ex) {
        assertNull(ex.getMessage());
        assertEquals(500, ex.getCode());
    }
    Mockito.verify(amazonDynamoDB, times(0)).shutdown();
    Mockito.verify(awsCredentialsProvider, times(0)).close();
}