我已经使用Spring Cloud Function编写了一个具有可选请求正文的函数。当主体具有内容时，一切都会起作用，但如果没有内容，则函数的输入将变为LinkedMultiValueMap，并且响应对象将包装在数组中。
我已经创建了一个最小的函数并进行了测试以说明问题，但是，尽管我可以想象为什么在不提供任何内容的情况下输入类型为何变成LinkedMultiValueMap，但是感觉就像是一个错误。是一个错误还是我只是做错了什么？
还有，当没有请求正文时，将响应包装在数组中的可能原因是什么？
这是我的最小功能
@Bean
Function<String, Integer> letterCount() {
return value -> StringUtils.isEmpty(value) ? 0 : value.length();
}
这是我的考验
@RunWith(SpringRunner.class)
@FunctionalSpringBootTest
public class LetterCountTestInt extends FunctionTestBase {
private MockMvc mockMvc;
@Autowired
private WebApplicationContext webApplicationContext;
@Before
public void setUp() {
mockMvc = webAppContextSetup(webApplicationContext).build();
}
@Test
public void testLetterCount() throws Exception {
//final String input = "blah";
final String input = "";
final MvcResult mvcResult = mockMvc.perform(post("/letterCount")
.content(input.getBytes(StandardCharsets.UTF_8))
.headers(createHttpHeaders()))
.andReturn();
mockMvc.perform(asyncDispatch(mvcResult))
.andExpect(status().isOk())
.andExpect(content().string(String.valueOf(input.length())));
}
}
这是我未在请求正文中提供内容时得到的堆栈跟踪
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.ClassCastException: class org.springframework.util.LinkedMultiValueMap cannot be cast to class java.lang.String (org.springframework.util.LinkedMultiValueMap is in unnamed module of loader 'app'; java.lang.String is in module java.base of loader 'bootstrap')
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1013)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
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.test.web.servlet.MockMvc.perform(MockMvc.java:182)
at c.a.b.p.LetterCountTestInt.testLetterCount(LetterCountTestInt.java:46)
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.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.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
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.ClassCastException: class org.springframework.util.LinkedMultiValueMap cannot be cast to class java.lang.String (org.springframework.util.LinkedMultiValueMap is in unnamed module of loader 'app'; java.lang.String is in module java.base of loader 'bootstrap')
at org.springframework.cloud.function.core.FluxFunction.lambda$apply$0(FluxFunction.java:47)
at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onNext(FluxMapFuseable.java:107)
at reactor.core.publisher.FluxJust$WeakScalarSubscription.request(FluxJust.java:99)
at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.request(FluxMapFuseable.java:162)
at reactor.core.publisher.MonoCollectList$MonoBufferAllSubscriber.onSubscribe(MonoCollectList.java:90)
at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onSubscribe(FluxMapFuseable.java:90)
at reactor.core.publisher.FluxJust.subscribe(FluxJust.java:70)
at reactor.core.publisher.FluxMapFuseable.subscribe(FluxMapFuseable.java:63)
at reactor.core.publisher.MonoCollectList.subscribe(MonoCollectList.java:59)
at reactor.core.publisher.MonoFlatMap.subscribe(MonoFlatMap.java:60)
at reactor.core.publisher.Mono.subscribe(Mono.java:3694)
at org.springframework.web.servlet.mvc.method.annotation.ReactiveTypeHandler$DeferredResultSubscriber.connect(ReactiveTypeHandler.java:440)
at org.springframework.web.servlet.mvc.method.annotation.ReactiveTypeHandler.handleValue(ReactiveTypeHandler.java:155)
at org.springframework.web.servlet.mvc.method.annotation.ResponseBodyEmitterReturnValueHandler.handleReturnValue(ResponseBodyEmitterReturnValueHandler.java:139)
at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:82)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:119)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)
at org.springframework.test.web.servlet.TestDispatcherServlet.service(TestDispatcherServlet.java:71)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
at org.springframework.mock.web.MockFilterChain$ServletFilterProxy.doFilter(MockFilterChain.java:166)
at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:133)
at org.springframework.test.web.servlet.MockMvc.perform(MockMvc.java:182)
at c.a.b.p.LetterCountTestInt.testLetterCount(LetterCountTestInt.java:41)
... 31 more