本文介紹了單元測試中的SpringBoot@Auowired返回NullPointerException的處理方法，對大家解決問題具有一定的參考價值，需要的朋友們下面隨著小編來一起學習吧！
問題描述
我有一個用@SERVICE注釋的類(HttpHandler)。我正在為這個服務類編寫單元測試用例。
我在我的測試類中使用了@AuTower注釋來獲取服務的對象。然而，當我運行單元測試時，它返回NullPOinterException。有人能幫幫我嗎？
服務等級代碼如下：
@Service
public class HttpHandler {
private static final Logger logger = LoggerFactory.getLogger(HttpHandler.class);
/**
* Build the request and Perform Http Get request with headers
* @param url
* @param httpHeaders
* @param responseClass
* @param <T>
* @param <R>
* @return
*/
public <T,R> ResponseEntity<T> sendPost(String url, HttpHeaders httpHeaders, R requestBody, Class<T> responseClass) {
//create an instance of rest template
RestTemplate restTemplate = new RestTemplate();
HttpEntity<R> entity = new HttpEntity<R>(requestBody, httpHeaders);
logger.info("POST request to " + url + " with body: " + JsonUtil.jsonizeExcludeNulls(requestBody));
//make an HTTP POST request with headers
ResponseEntity<T> response = restTemplate.exchange(url, HttpMethod.POST, entity, responseClass);
logger.info("POST" + url + ": " + JsonUtil.jsonize(response));
return response;
}
}
我正在為POST調用編寫單元測試用例。下面是POST調用的單元測試
公共類HttpHandlerTest{
@Autowired
HttpHandler httpHandler;
@Test
public void testSuccessPostUser() throws Exception{
String baseUrl = "http://localhost:8080/users";
List<String> messages = new ArrayList<>();
messages.add("Hi");
User user = new User();
user.setId(1);
user.setName("John");
user.setAge(22);
user.setMessages(messages);
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.setContentType(MediaType.APPLICATION_JSON);
httpHeaders.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON));
HttpEntity<User> httpEntity = new HttpEntity<>(user, httpHeaders);
ResponseEntity<User> actual = httpHandler.sendPost(baseUrl, httpHeaders, user, User.class);
//verify request succeed
assertEquals(HttpStatus.CREATED, actual.getStatusCode());
assertEquals(201, actual.getStatusCodeValue());
assertTrue(actual.toString().contains("id"));
}
}
它顯示以下錯誤：
java.lang.NullPointerException
at com.xyz.provisioning.xyz.utils.HttpHandlerTest.testSuccessPostUser(HttpHandlerTest.java:41)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:686)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:149)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:140)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:84)
at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
推薦答案
對于JUNIT 5(如注釋中所述)，您只需在測試類的頂部添加@SpringBootTest。
@SpringBootTest
class HttpHandlerTest{
// ...
}
您不需要添加@ExtendWith(SpringExtension.class)，因為是由批注@SpringBootTest自動導入的。
要獲得與Junit4相同的結果：
@RunWith(SpringRunner.class)
@SpringBootTest
class HttpHandlerTest{
// ...
}
這篇關于單元測試中的SpringBoot@Auowired返回NullPointerException的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，
