Question

500 - Servlet execution threw an exception

严重: Servlet.service() for servlet [AddCustomerServlet] in context with path [/Custm] threw exception [Servlet execution threw an exception] with root cause
java.lang.Error: Unresolved compilation problems:
ConvertUtils cannot be resolved
DateLocaleConverter cannot be resolved to a type
BeanUtils cannot be resolved

at cn.guet.utils.WebUtils.request2Bean(WebUtils.java:21)
at cn.guet.web.controller.AddCustomerServlet.doGet(AddCustomerServlet.java:22)
at cn.guet.web.controller.AddCustomerServlet.doPost(AddCustomerServlet.java:39)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)

Answer 1

是因为当commons-fileupload包从版本1.0升到1.1时，DeferredFileOutputStream.class被移走了。如果Tomcat使用1.1及其以上版本，你得为它找到这个类。

解决方法:

进入目录：$CATALINA/server/webapps/manager/WEB-INF/lib，检查是否存在三个包：

commons-io
catalina-manager.jar
commons-fileupload.jar
如果缺少commons-io，拷一个过来。

或者直接使用老版本的commons-fileupload.jar

Answer 2

ConvertUtils cannot be resolved // ConvertUtils 找不到
DateLocaleConverter cannot be resolved to a type //有一个数据找不到
BeanUtils cannot be resolved// BeanUtils找不到
多半是你servlet参数和 对象问题 能把你代码放上来看看最好 光看这个抛得异常解决不了什么问题