public static BadRequestException clusterAlreadyExists(String clusterName) {
    return new BadRequestException("cluster already exists for clusterName:%s", clusterName);
  }
@Test
  public void testClusterAlreadyExists(){
    BadRequestException clusterAlreadyExists = BadRequestException.clusterAlreadyExists(clusterName);
    assertEquals("cluster already exists for clusterName:test", clusterAlreadyExists.getMessage());
  }