Controller Tests Gives NullPointerException

[msousa-fp]

Hi, I have an issue running Controller Tests,

I create a StockController just like the ProductController you have!

@Component
public class StockController implements StockResource {
    private UseCaseExecutor useCaseExecutor;
    private GetAllStocksUseCase getAllStocksUseCase;
    
    @Autowired
    public StockController(UseCaseExecutor useCaseExecutor,
                           GetAllStocksUseCase getAllStocksUseCase) {
        this.useCaseExecutor = useCaseExecutor;
        this.getAllStocksUseCase = getAllStocksUseCase;
    }

    @Override
    public CompletableFuture<List<StockResponse>> getAllStocks(
            @RequestParam(value="materialNumber", required=false) String materialNumber,
            @RequestParam(value="storageLocation", required=false) String  storageLocation,
            @RequestParam(value="plant", required=false) String  plant) {
        return useCaseExecutor.execute(
                getAllStocksUseCase,
                GetAllStocksInputMapper.map(
                        materialNumber,
                        storageLocation,
                        plant
                ),
                (outputValues) -> StockResponse.from(outputValues.getStockList()));
    }

And create a StockControllerTest

@RunWith(SpringRunner.class)
@WebMvcTest(value = StockController.class, secure = false)
public class StockControllerTest {

    @MockBean
    private GetAllStocksUseCase getAllStocksUseCase;
    @SpyBean
    private UseCaseExecutorImpl useCaseExecutor;
    @Autowired
    private MockMvc mockMvc;

    @Configuration
    @ComponentScan(basePackages = {"com.example.presenter.rest.api.stock"})
    static class Config {
    }

    @Test
    public void deliveryOrderReturnsOk() throws Exception {

        Stock stock = TestEntityGenerator.randomStock();

        GetAllStocksUseCase.InputValues input = GetAllStocksInputMapper.map(
                stock.getMaterialNumber(),
                stock.getStorageLocation(),
                stock.getPlant());

        GetAllStocksUseCase.OutputValues output = new GetAllStocksUseCase.OutputValues(Collections.singletonList(stock));

        doReturn(output)
                .when(getAllStocksUseCase)
                .execute(input);

        final String request =
                "/api/stocks?materialNumber=" +
                        stock.getMaterialNumber() + "&plant=" + stock.getPlant() + "&storageLocation=" + stock.getStorageLocation();

        RequestBuilder payload = asyncGetRequest(request);

        mockMvc.perform(payload)
                .andExpect(status().isOk())
                .andExpect(content().contentType(MediaType.APPLICATION_JSON_UTF8))
                .andExpect(jsonPath("$.[0].materialNumber", is(stock.getMaterialNumber())))
                .andExpect(jsonPath("$.[0].plant", is(stock.getPlant())))
                .andExpect(jsonPath("$.[0].storageLocation", is(stock.getStorageLocation())))
                .andExpect(jsonPath("$.[0].availableQuantity", is(stock.getAvailableQuantity())))
                .andExpect(jsonPath("$.[0].quantity", is(stock.getQuantity())));
    }

    protected RequestBuilder asyncGetRequest(String url) throws Exception {
        return asyncDispatch(mockMvc.perform(get(url))
                .andExpect(request().asyncStarted())
                .andReturn());
    }
}

When I run the test it gives a NullPointException on OutputValues

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException

	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1013)
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:897)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)
	at org.springframework.test.web.servlet.TestDispatcherServlet.service(TestDispatcherServlet.java:71)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	at org.springframework.mock.web.MockFilterChain$ServletFilterProxy.doFilter(MockFilterChain.java:166)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:133)
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:133)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:133)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:133)
	at org.springframework.test.web.servlet.MockMvc.perform(MockMvc.java:182)
	at com.example.presenter.rest.api.stock.StockControllerTest.deliveryOrderReturnsOk(StockControllerTest.java:61)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:74)
	at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:84)
	at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
	at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
	at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: java.lang.NullPointerException
	at com.example.presenter.rest.api.stock.StockController.lambda$getAllStocks$0(StockController.java:37)
	at java.util.concurrent.CompletableFuture.uniApply(CompletableFuture.java:602)
	at java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:577)
	at java.util.concurrent.CompletableFuture$Completion.exec(CompletableFuture.java:443)
	at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
	at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
	at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
	at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)

Could you help me with this problem? It seems that it does not run the execute of useCase before the outputMapper so the OutputValues are null

[eliostvs]

Hi, have you try to use mockito.equal() or mockito.any() in the getAllStocksUseCase mock?