org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is ja

HTTP Status 500 – Internal Server Error

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Type Exception Report

Message Handler dispatch failed; nested exception is java.lang.NoClassDefFoundError: com/fasterxml/jackson/databind/ObjectMapper

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.NoClassDefFoundError: com/fasterxml/jackson/databind/ObjectMapper
	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1055)
	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:635)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)

Root Cause

java.lang.NoClassDefFoundError: com/fasterxml/jackson/databind/ObjectMapper
	com.lzy.controller.UserController.json1(UserController.java:18)
	java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	java.base/java.lang.reflect.Method.invoke(Method.java:566)
	org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
	org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
	org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:888)
	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:635)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)

Root Cause

java.lang.ClassNotFoundException: com.fasterxml.jackson.databind.ObjectMapper
	org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1308)
	org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1136)
	com.lzy.controller.UserController.json1(UserController.java:18)
	java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	java.base/java.lang.reflect.Method.invoke(Method.java:566)
	org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
	org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
	org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:888)
	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:635)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)

Note The full stack trace of the root cause is available in the server logs.

解决方法：

1.