others-how to solve `java.lang.NoClassDefFoundError: com/alibaba/fastjson/JSONObject` error when dealing with json in java?

1. Purpose

In this post, I will demonstrate how to solve the following error when using java to deal with json:

Servlet[appServlet]的Servlet.service（）Handler processing failed; nested exception is java.lang.NoClassDefFoundError: com/alibaba/fastjson/JSONObject
java.lang.NoClassDefFoundError: com/alibaba/fastjson/JSONObject
    at com.app.controllers.AppController.getTimerOrderInfo(AppController.java:80)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:747)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:676)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:863)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)
    at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:492)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:165)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:451)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1201)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:654)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:317)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)

2. Solution

2.1 Debug

classpath:

[[email protected] tomcat-appwebssl]# find . -name "*.jar"
./lib/websocket-api.jar
./lib/tomcat-i18n-ja.jar
./lib/jsp-api.jar
./lib/catalina.jar
./lib/servlet-api.jar
./lib/tomcat-jdbc.jar
./lib/jasper.jar
./lib/tomcat7-websocket.jar
./lib/tomcat-i18n-ru.jar
./lib/ecj-4.4.2.jar
./lib/catalina-tribes.jar
./lib/jasper-el.jar
./lib/tomcat-util.jar
./lib/tomcat-api.jar
./lib/annotations-api.jar
./lib/tomcat-i18n-zh-CN.jar
./lib/catalina-ant.jar
./lib/catalina-ha.jar
./lib/tomcat-i18n-es.jar
./lib/el-api.jar
./lib/tomcat-i18n-ko.jar
./lib/tomcat-i18n-fr.jar
./lib/tomcat-coyote.jar
./lib/tomcat-i18n-de.jar
./lib/tomcat-dbcp.jar
./app/lib/javax.inject-1.jar
./app/lib/lucene-highlighter-5.3.1.jar
./app/lib/jsr311-api-1.1.1.jar
./app/lib/commons-pool2-2.3.jar
./app/lib/guava-18.0.jar
./bin/bootstrap.jar
./bin/tomcat-juli.jar
./bin/commons-daemon.jar

2.2 The solution to this problem

According to the debug log, we can see that the fastjson jar is missing in our classpath, so copy it to the classpath:

./lib/fastjson-1.2.78.jar

3. Summary

In this post, I demonstrated how to solve the java.lang.NoClassDefFoundError: com/alibaba/fastjson/JSONObject. That’s it, thanks for your reading.