Mockito is returning "java.lang.IllegalArgumentException: URI is not absolute" in RestTemplate.exchange. I am not sure why this is happening because it seems I am mocking the restTemplate properly and since I am seeing that exception, it seems that RestTemplate is not a mock.

Here is my class

@Component
public class RestTemplateWrapper {
  private static final Logger LOGGER = LoggerFactory.getLogger(RestTemplateWrapper.class);
  
  public <T> ResponseEntity<T> callWebServiceGET(String url,HttpEntity<?> httpEntity,
      ParameterizedTypeReference<T> parameterizedTypeReference) {

    RestTemplate restTemplate = new RestTemplate();
    ResponseEntity<T> response=null;
    LOGGER.trace("Entered callWebServiceGET");
    LOGGER.info("Calling WebService {}", url);
    try {
      response=restTemplate.exchange(url, HttpMethod.GET, httpEntity, parameterizedTypeReference);
    } catch (HttpClientErrorException e) {
      if (HttpStatus.NOT_FOUND.equals(e.getStatusCode())) {
        LOGGER.error("Service Unavailable - Code 404 returned. "   url   e.getMessage());
      } else if (HttpStatus.UNAUTHORIZED.equals(e.getStatusCode())) {
        LOGGER.error("Token Expired- Code 401 returned. "   e.getMessage());
      } else if (HttpStatus.BAD_REQUEST.equals(e.getStatusCode())) {
        LOGGER.error("Bad Input, 400 returned.{} {} ", url , e.getMessage(), e);
      } else {
        LOGGER.error("WEB Service Failure. "   e.getMessage());
      }
    }
    return response;
  }

}

And here is my TestCase:

@PrepareForTest({RestTemplateWrapper.class})
public class RestTemplateWrapperTest  {
  
  @Mock
  private RestTemplate mockRestTemplate;
  @InjectMocks
  private RestTemplateWrapper webUtils;
  @Before
  public void setUp() throws Exception {
    MockitoAnnotations.initMocks(this);
  }
  @Test
  public void callWebServiceGET_OK()  {
    HttpEntity<String> httpEntity= new ResponseEntity<>(HttpStatus.OK);
    ResponseEntity<String> entityResponse=new ResponseEntity<>("MOCK_RESPONSE", HttpStatus.OK);
    when(mockRestTemplate.exchange(eq("/objects/get-objectA"), eq(HttpMethod.GET), eq(httpEntity),any(
        ParameterizedTypeReference.class))).thenReturn(
        entityResponse);
    ResponseEntity<String> mockResponse= webUtils.callWebServiceGET("",null,  new ParameterizedTypeReference<String>(){
    });
    //verify(mockRestTemplate,times(1)).exchange(Matchers.anyString(), Matchers.any(), Matchers.any());
     Assert.assertEquals("MOCK_RESPONSE",mockResponse.getBody());
  }
  
}

The response:

URI is not absolute
java.lang.IllegalArgumentException: URI is not absolute
    at java.net.URI.toURL(URI.java:1088)
    at org.springframework.http.client.SimpleClientHttpRequestFactory.createRequest(SimpleClientHttpRequestFactory.java:145)
    at org.springframework.http.client.support.HttpAccessor.createRequest(HttpAccessor.java:87)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:727)
    at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:666)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:604)
    at com.project.di.tp.purchaseorderservice.utils.RestTemplateWrapper.callWebServiceGET(RestTemplateWrapper.java:29)
    at com.project.di.tp.purchaseorderservice.utils.RestTemplateWrapperTest.callWebServiceGET_OK(RestTemplateWrapperTest.java:51)

Any idea about how to solve this issue? I have been trying like 4 hours.

CodePudding user response：

Although it is not stated explicitly in the JavaDocs it is the case that you have to provide an absolute URL there.

This is because you do nowhere provide a base URL where a relative URL would be relative to. You could not enter "/objects/get-objectA" as URL in your browser either.

So I would suggest that you use something like "http://example.com/objects/get-objectA" instead for the first parameter:

when(mockRestTemplate.exchange(
        eq("http://example.com/bla"), 
        eq(HttpMethod.GET), 
        isNull(HttpEntity.class), 
        any(ParameterizedTypeReference.class))).
    thenReturn(entityResponse);

ResponseEntity<String> mockResponse =
    webUtils.callWebServiceGET(
        "http://example.com/bla", 
        null, 
        new ParameterizedTypeReference<String>(){});

Please note that the call to webUtils.callWebServiceGET with given parameters would not make Mockito return the wanted answer, so I changed for one the URL in the call to the absolute URL you are expecting in the Mockito.when and also changed the parameter expected there to be a typed null (typed to match the method signature).

CodePudding user response：

I found the solution, it seems the problem is that my class is RestTemplateWrapper is creating a instance inside callWebServiceGET therefore mockito can`t mock that object. If if set the object outside the method, it works but I dont want to do that.

Is there any way to mock a object that is inside a method?