java - 如何将@RequestBody 值传递给转发 Controller Spring MVC

Question

我必须使用 @RequestBody 的值来转发 Controller 。当我将 JSON 作为请求主体传递时，它将从一个 Controller 转发到另一个 Controller 。但是它给第二个 Controller java.io.IOException

MyController.java

@Controller
public class MyController {

/* 
Request JSON like  
{"personeId":"123789","personName":"Fitz"}
*/
@RequestMapping(value = "/myapp/first/", method = RequestMethod.POST, 
        consumes = { "application/json" })
public String authorize(@RequestBody Person person) {
    //Looking good
    if(Validator.validatePerson(perosn)) {
        return "forward:/myapp/second/";
    } else {
        return "forward:/myapp/secondError/";
    }
}

@RequestMapping(value = "/myapp/second/", method = RequestMethod.POST, 
        consumes = { "application/json" })
public @ResponseBody String login(@RequestBody Person person) {
    // Not able to get Person object here.
    // Getting java.io.IOException: Stream closed :( 
    System.out.println("---> "+person.getPersonName());
    return "success";
}

@RequestMapping(value = "/myapp/secondError/", method = RequestMethod.POST,
        consumes = { "application/json" })
public @ResponseBody String loginError() {
    return "error";
}
}

堆栈跟踪

org.apache.catalina.core.ApplicationDispatcher invoke
SEVERE: Servlet.service() for servlet dispatcher threw exception
java.io.IOException: Stream closed
    at org.apache.catalina.connector.InputBuffer.readByte(InputBuffer.java:339)
    at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:94)
    at java.io.FilterInputStream.read(FilterInputStream.java:83)
    at java.io.PushbackInputStream.read(PushbackInputStream.java:139)
    at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.readWithMessageConverters(RequestResponseBodyMethodProcessor.java:168)
    at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.resolveArgument(RequestResponseBodyMethodProcessor.java:105)
    at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:77)
    at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:162)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:129)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:777)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:706)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:868)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:644)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:301)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:721)
    at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:466)
    at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:391)
    at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:318)
    at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:168)
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:303)
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1228)
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1011)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:955)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:868)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:644)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:301)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:136)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:74)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:516)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1015)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:652)
    at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:222)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1575)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1533)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)

所以有什么方法可以用 Spring MVC 实现这个场景。

Answer 1

你得到异常是因为 @RequestBody 注释读取底层 servlet 输入流并使用它，所以你不能读取它两次。

如果你仔细观察堆栈跟踪，你可以注意到来源

org.apache.catalina.connector.InputBuffer.readByte(InputBuffer.java:339)

您正在尝试(重新)从已关闭的流中读取数据。

如果你想保留第一个 Controller ，你必须改变第二个，你可以选择例如重定向到第二个 Controller 并将对象放入 session 中，或者从第二个 Controller 中提取一个方法来处理业务逻辑并从第一个 Controller 调用它。

如果您可以将 json 放在 http 调用的参数中(授权)，您可以避免这个问题，但是(授权)它不再是 REST ednpoint，而是类似于“简单”的 http 集成。