Jackson 和 fastJSON 导包异常

刺骨的言语ヽ痛彻心扉 2022-10-14 00:45 137阅读 0赞

# 内容 #

## 一、异常信息 ##

HTTP Status 400 - type Status report

message

org.springframework.http.converter.HttpMessageNotWritableException: No converter found for return value of type

## 二、解决办法 ##

### 1、异常 ###

1.  异常截图  
    ![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p6dmFy_size_16_color_FFFFFF_t_70]
2.  详细信息

exception
    org.springframework.http.converter.HttpMessageNotWritableException: No converter found for return value of type: class com.yy.homework.qo.JsonResult
    	org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:226)
    	org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:180)
    	org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:82)
    	org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:119)
    	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877)
    	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783)
    	org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
    	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)
    	org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
    	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974)
    	org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:877)
    	javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
    	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851)
    	javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
    	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    note The full stack trace of the root cause is available in the Apache Tomcat/7.0.37 logs.

1.  错误原因  
    使用 JSON 时，**导入的包是 fastJSON 或者没有导包**，**我们应该导入 jackson 包**

### 2、解决 ###

导入 Jackson 包即可，fastJSON 包有时候有问题

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p6dmFy_size_16_color_FFFFFF_t_70]: /images/20221014/c80df8b07bdd4c6eb470edf98a8e26d2.png