Unable to handle .isPresent() while creating Juint test cases

Question

if (clientDetailsRepository.findIDByClientName(clientDetailRequest.getClientName()).isPresent()) {
            return CommonUtils.getResponseObject(HttpStatus.CONFLICT, req,
                    "Client with Client Name " + clientDetailRequest.getClientName() + " is already present",
                    false);
        }

while writing the Junit test case for the following :

@Test
public void setClientDetailsTest() {
    Optional<Long> opt = Optional.of(20l);
    when(clientDetailsRepository.findIDByClientName(Mockito.anyString())).thenReturn(opt);
            ResponseEntity<Object> response =  clientService.setClientDetails(req,ClientDetails());
        assertNotNull(response);
    }
    

What I have observed is that isPresent() is always returning false and it is never going inside if Statement

Answer 1

I think the issue is related to ArgumentMatcher. So try to pass the correct value, not a matcher. Example:

@Test
public void setClientDetailsTest() {
    String clientName = "testClient";
    ClientDetailRequest clientDetailRequest = new ClientDetailRequest();
    clientDetailRequest.setClientName(clientName);

    Optional<Long> opt = Optional.of(20L);
    when(clientDetailsRepository.findIDByClientName(clientDetailRequest.getClientName())).thenReturn(opt);

    ResponseEntity<Object> response = clientService.setClientDetails(req, clientDetailRequest);

    assertNotNull(response);
}