问题描述
- ClassNotFoundException: com.google.gson.Gson
-
Servlet.service() for servlet [ns] in context with path [/EC] threw exception [Handler processing failed; nested exception is java.lang.NoClassDefFoundError: com/google/gson/Gson] with root cause
java.lang.ClassNotFoundException: com.google.gson.Gson
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1720)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1571)
at com.ns.controllers.impl.systemDevice.SystemManageImpl.SendDeviceControlOrder(SystemManageImpl.java:307)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:827)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
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 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 com.alibaba.druid.support.http.WebStatFilter.doFilter(WebStatFilter.java:123)
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:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
解决方案
java.lang.ClassNotFoundException: com.google.gson.Gson”
解析json之com.google.gson.Gson
解析json之com.google.gson.Gson
解决方案二：
少了 Google Gson（gson-xxx.jar）
下载地址：http://download.csdn.net/detail/a771948524/6668573
解决方案三：
http://jingyan.baidu.com/article/3f16e003ca120e2591c103ac.html
解决方案四：
1.需要的Jar包
1） Google Gson（gson-xxx.jar）下载地址：http://code.google.com/p/google-gson/downloads/list
2）JUnit4
- 应用实例代码
下载地址：http://download.csdn.net/source/3499627
http://www.cnblogs.com/cyjch/archive/2012/02/15/2352792.html
解决方案五：
java.lang.ClassNotFoundException为常见的Java错误之一，即没有找到对应的class文件，一般后面都会给出缺少的类文件名称，比如你的是com.google.gson.Gson
通常运行之前需要先看下你的工程java源码中是否有红色叉，有的话先解决了，一般可以避免类似的问题出现；
如果出现了这种情况，直接去晚上找对应的jar包下载，推荐一个网站http://findjar.com/index.x，直接输入你要找的类即可，这个给出的链接都是官方的，比较靠谱。
解决方案六：
库没有加载上，你要把gson的库加载过来。
可以直接在配置文件里面增加一个标记自动加载：
http://mvnrepository.com/artifact/com.google.code.gson/gson/2.3.1#gradle
解决方案七：
当然是要先导入jar包，然后Build Path啊，然后再配置使用条件，才能正常使用
时间： 2024-08-02 11:33:45