@Override
  public boolean databaseExists(String databaseName) throws CatalogException {
    checkArgument(!StringUtils.isNullOrEmpty(databaseName));

    return listDatabases().contains(databaseName);
  }
@Test
  public void testDatabaseExists() {
    assertTrue(catalog.databaseExists(TEST_DEFAULT_DATABASE));
    assertFalse(catalog.databaseExists(NONE_EXIST_DATABASE));
  }