Servlets 类找不到异常，说明如下：服务器遇到内部错误（），导致其无法满足此请求

控制台中的错误：

Dec 13, 2015 12:45:54 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Allocate exception for servlet LoginController
java.lang.ClassNotFoundException: flexController.LoginController
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1676)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1521)
    at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:415)
    at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:397)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:118)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1062)
    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:813)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:135)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:395)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:250)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)


my servlet is:
package flexController;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;



/**
 * Servlet implementation class LoginController
 */
@SuppressWarnings("serial")
@WebServlet("/LoginController")
public class LoginController extends HttpServlet {

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String un=request.getParameter("username");
        String pw=request.getParameter("password");

        if(un.equals("admin") && pw.equals("admin"))
        {
            response.sendRedirect("home.jsp");
            return;
        }
        else
        {
            response.sendRedirect("error.jsp");
            return;
        }
    }
}

我的web.xml是：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0"
 metadata-complete="true">
  <display-name>Flex1.1</display-name>
<welcome-file-list>
    <welcome-file>login.jsp</welcome-file>
  </welcome-file-list>
  <servlet>
  <description></description>
    <display-name>LoginController</display-name>
    <servlet-name>LoginController</servlet-name>
    <servlet-class>flexController.LoginController</servlet-class>
  </servlet>

<servlet-mapping>
    <servlet-name>LoginController</servlet-name>
    <url-pattern>/LoginController</url-pattern>
  </servlet-mapping>


</web-app>

Flex1.1
login.jsp
登录控制器
登录控制器
flexController.LoginController
登录控制器
/登录控制器

---

我正在使用servlet编写一个简单的登录页面，登录后会重定向到成功页面或错误页面。

测试了您的代码。在我这一步工作正常。请完成一个干净的构建，然后重试。您如何调用此servlet？感谢Prince，它现在工作正常，我刚刚删除了整个项目并将其导入。测试了您的代码。在我结束时工作正常。进行干净的构建并重试。您如何调用此servlet？谢谢Prince，现在工作正常，我刚刚删除了整个项目并将其导入回。