关于我的Servlet的错误

Question

java.lang.ClassNotFoundException: com.vv.view.LoginCLServlet
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1128)
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:103)
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.Http11Processor.process(Http11Processor.java:861)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:744)这个异常代表了什么问题？刚刚没贴这个异常真不应该

Answer 1

com.vv.view.LoginCLServlet
这个是你自己写的类？
看看这个类编译好了没

Answer 2

你好，我编译那个类，控制台出现十月 27, 2014 1:43:58 下午 org.apache.catalina.core.StandardWrapperValve invoke
信息: Servlet LoginCLServlet is currently unavailable，这是什么情况呢？

Answer 3

你好，是这样的，这三个servlet分别在三个不同的包，LoginServlet在包com.vv.view，LoginCLServlet在包com.vv.Controler，MainFrame在包com.vv.main，但是部署后，竟然出现了这个异常java.lang.ClassNotFoundException:com.vv.view.LoginCLServlet，LoginCLServlet明明不再vv.com.view这个包里呀，这到底是什么问题呢？

Answer 4

访问地址：http://localhost:8080/login/loginServlet<?xml version="1.0" encoding="ISO-8859-1"?><web-app xmlns="http://java.sun.com/xml/ns/javaee"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
                      http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
  version="3.0"
  metadata-complete="true">      <description>
      Servlet and JSP Examples.
    </description>
    <display-name>Servlet and JSP Examples</display-name>
    
    <servlet>
      <servlet-name>loginServlet</servlet-name>
      <servlet-class>com.test.LoginServlet</servlet-class>
    </servlet>
   <servlet-mapping>
   <servlet-name>loginServlet</servlet-name>
   <url-pattern>/loginServlet</url-pattern>
   </servlet-mapping>
    <servlet>
      <servlet-name>loginCLServlet</servlet-name>
      <servlet-class>com.view.LoginCLServlet</servlet-class>
    </servlet>
   <servlet-mapping>
   <servlet-name>loginCLServlet</servlet-name>
   <url-pattern>/loginCLServlet</url-pattern>
   </servlet-mapping>
    <servlet>
      <servlet-name>mainFrame</servlet-name>
      <servlet-class>com.end.MainFrame</servlet-class>
    </servlet>
   <servlet-mapping>
   <servlet-name>mainFrame</servlet-name>
   <url-pattern>/mainFrame</url-pattern>
   </servlet-mapping>
    
</web-app>
package com.test;import java.io.IOException;
import java.io.PrintWriter;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 LoginServlet
 */public class LoginServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public LoginServlet() {
        super();
        // TODO Auto-generated constructor stub
    } /**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //处理字符编码
        response.setContentType("text/html;charset=utf-8");
        response.setCharacterEncoding("utf-8");
        PrintWriter out = response.getWriter();
        //返回一个界面
        try {
out.println("<h1>用户登录</h1>");
out.println("<form action='/login/loginCLServlet' method='post'>");
out.println("用户名:<input type='text' name='username'><br/>");
out.println("密 码:<input type='password' name='password'><br/>");
out.println("<input type='submit' value='登录' /><br/>");
out.println("</form>");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
         
    }
 
    /**
     * The doPost method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to post.
     * 
     * @param request the request send by the client to the server
     * @param response the response send by the server to the client
     * @throws ServletException if an error occurred
     * @throws IOException if an error occurred
     */
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        this.doGet(request, response);
         
    }}package com.view;import java.io.IOException;
import java.io.PrintWriter;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 LoginCLServlet
 */
public class LoginCLServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public LoginCLServlet() {
        super();
        // TODO Auto-generated constructor stub
    } /**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
     this.doPost(request, response);
        
    }
 
 
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
     response.setContentType("text/html;charset=utf-8");
        response.setCharacterEncoding("utf-8");
        PrintWriter out = response.getWriter();
        //out.println("用户检验中....");
         
        String username = request.getParameter("username");
        String password = request.getParameter("password");
         
      try {
       if ("zhangsan".equalsIgnoreCase(username)&&"123".equalsIgnoreCase(password)) {
response.sendRedirect("/login/mainFrame");
} else {
response.sendRedirect("/login/loginServlet");
}

} catch (Exception e) {
// TODO: handle exception
}
         
    }}
package com.end;import java.io.IOException;
import java.io.PrintWriter;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 MainFrame
 */
public class MainFrame extends HttpServlet {
private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public MainFrame() {
        super();
        // TODO Auto-generated constructor stub
    } /**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
 
        response.setContentType("text/html;charset=utf-8");
        response.setCharacterEncoding("utf-8");
        PrintWriter out = response.getWriter();
         
        out.println("<h1>主界面</h1>");
    }
 
 
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        this.doGet(request, response);
         
    }}