我的单元测试中为NullPointerException

Question

The first function throws NullPointerException , why does this happen? The second function doesn't have any problems.

UrlShortenerTests.Java

//Test de redireccion si la url corta existe
@Test
public void thatRedirectToReturnsTemporaryRedirectIfKeyExists()
        throws Exception {
    when(shortURLRepository.findByKey("someKey")).thenReturn(new ShortURL("someKey", "http://example.com/", null, null, null,
            null, 307, true, null, null));

    mockMvc.perform(get("/l{id}", "someKey")).andDo(print())
            .andExpect(status().isAccepted());
}

//Test de redireccion si la url corta no existe
@Test
public void thatRedirecToReturnsNotFoundIdIfKeyDoesNotExist()
        throws Exception {
    when(shortURLRepository.findByKey("someKey")).thenReturn(null);

    mockMvc.perform(get("/l{id}", "someKey")).andDo(print())
            .andExpect(status().isNotFound());
}

Stack trace:

test.java.urlshortener2014.web.rest.UrlShortenerTests > thatRedirectToReturnsTemporaryRedirectIfKeyExists FAILED
    org.springframework.web.util.NestedServletException at UrlShortenerTests.java:74
        Caused by: java.lang.NullPointerException at UrlShortenerTests.java:74

Answer 1

After reviewing your code, you must mock all the injections in UrlShortnenerOldBurgundy . That includes WorkRepositorySponsor which is invoked in line 58 of your class UrlShortnenerOldBurgundy and causes the exception. Just add in UrlShortenerClass :

@Mock WorksRepositorySponsor worksRepositorySponsor;