No converter found for return value of type: class 类全路径

org.springframework.http.converter.HttpMessageNotWritableException: No converter found for return value of type: class 类全路径 org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:230) org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:181) org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:82) org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:123) org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879) org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793) org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) javax.servlet.http.HttpServlet.service(HttpServlet.java:626) org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) javax.servlet.http.HttpServlet.service(HttpServlet.java:733) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

原因： 经测试配置MVC试图解析起之后，返回json格式的数据就会抱此类错误

解决方法： 在配置文件中加入mvc:annotation-driven/此标签可以解决此类错误！