Servlet:SEVERE:为servlet分配异常

Question

以下stacktrace是我尝试访问servlet时获得的,这似乎从Tomcat管理器运行良好.

11 Sep, 2012 11:50:12 AM org.apache.catalina.core.ApplicationContext log
INFO: Marking servlet LoginServlet as unavailable
11 Sep, 2012 11:50:12 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Allocate exception for servlet LoginServlet
java.lang.Error: Unresolved compilation problems: 
    The import javax.servlet cannot be resolved
    The import javax.servlet cannot be resolved
    The import javax.servlet cannot be resolved
    The import javax.servlet cannot be resolved
    The import javax.servlet cannot be resolved
    The import javax.servlet cannot be resolved
    HttpServlet cannot be resolved to a type
    ServletConfig cannot be resolved to a type
    ServletException cannot be resolved to a type
    HttpServlet cannot be resolved to a type
    ServletContext cannot be resolved to a type
    ServletException cannot be resolved to a type
    HttpServletRequest cannot be resolved to a type
    HttpServletResponse cannot be resolved to a type
    ServletException cannot be resolved to a type
    request cannot be resolved
    The method getLoggedin() from the type LoginHandler refers to the missing type ServletException
    The method destroy() of type LoginManager must override or implement a supertype method
    HttpServlet cannot be resolved to a type

    at com.login.servlets.LoginManager.<init>(LoginManager.java:5)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at java.lang.Class.newInstance0(Unknown Source)
    at java.lang.Class.newInstance(Unknown Source)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1149)
    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:827)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:129)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
    at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:877)
    at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:594)
    at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1675)
    at java.lang.Thread.run(Unknown Source)
11 Sep, 2012 12:05:12 PM org.apache.catalina.core.ApplicationContext log
INFO: Marking servlet Log4JInitServlet as unavailable
11 Sep, 2012 12:05:12 PM org.apache.catalina.core.StandardContext loadOnStartup
SEVERE: Servlet /logintest threw load() exception
java.lang.Error: Unresolved compilation problems: 
    The import javax.servlet cannot be resolved
    The import javax.servlet cannot be resolved
    The import javax.servlet cannot be resolved
    The import javax.servlet cannot be resolved
    The import org.apache cannot be resolved
    The import org.apache cannot be resolved
    HttpServlet cannot be resolved to a type
    ServletConfig cannot be resolved to a type
    ServletException cannot be resolved to a type
    ServletContext cannot be resolved to a type
    BasicConfigurator cannot be resolved
    PropertyConfigurator cannot be resolved
    BasicConfigurator cannot be resolved

    at com.logger.WebLogger.<init>(WebLogger.java:5)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at java.lang.Class.newInstance0(Unknown Source)
    at java.lang.Class.newInstance(Unknown Source)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1149)
    at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1026)
    at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4421)
    at org.apache.catalina.core.StandardContext.start(StandardContext.java:4734)
    at org.apache.catalina.core.StandardContext.reload(StandardContext.java:3461)
    at org.apache.catalina.manager.ManagerServlet.reload(ManagerServlet.java:943)
    at org.apache.catalina.manager.HTMLManagerServlet.reload(HTMLManagerServlet.java:557)
    at org.apache.catalina.manager.HTMLManagerServlet.doGet(HTMLManagerServlet.java:121)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.filters.CsrfPreventionFilter.doFilter(CsrfPreventionFilter.java:186)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:563)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
    at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:877)
    at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:594)
    at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1675)
    at java.lang.Thread.run(Unknown Source)

在eclipse类路径中使用的所有jar都可以在Tomcat lib文件夹中使用.webapp正在部署而没有任何错误日志,但是当我尝试访问一个servlet时,会发生此异常,并且我将其记录在tomcat日志中.有人能帮忙吗？

The package names are proper inside 'classes', also, the web.xml is proper. 

我不知道为什么会发生这种情况.还有一些其他的webapps,几乎使用相同的libs运行良好.期待一些人可以帮助我...

谢谢

Answer 1

最后,弄错了.这是eclipse构建引起的问题.由于构建不正确,类文件已损坏.我清理了整个项目,采取了新的构建,现在它工作正常.谢谢你的回复.