我已经使用 servlet 和 JSP 创建了登录页面。它适用于首次登录。但是在注销后，如果我尝试另一个登录 servlet 会被执行，因为我可以在 url 中看到它，但看不到输出。
验证.java
package servlets;
import java.sql.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class validate extends HttpServlet {
/**
*
* @param request
* @param response
* @throws ServletException
* @throws IOException
*/
public void doPost(HttpServletRequest request,HttpServletResponse
response)
throws ServletException,IOException
{
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
try{
String name=request.getParameter("email");
String pass=request.getParameter("password");
Class.forName("org.sqlite.JDBC");
Connection con= DriverManager.getConnection("jdbc:sqlite:C:\\SQLITE\\ MYDATABASE.DB");
Statement s=con.createStatement();
ResultSet rs;
rs = s.executeQuery("SELECT * FROM LOGIN WHERE EMAIL_ID='"+name+"' ");
if(rs.next())
{
if( (name.trim().equals(rs.getString(3).trim())) && (
pass.trim().equals(rs.getString(6).trim()) ) )
{
//New session creation
HttpSession session=request.getSession(true);
//setting attribute on session
session.setAttribute("user",name);
//send request to Welcome.jsp page
RequestDispatcher view =request.getRequestDispatcher("welcome.jsp");
view.forward(request, response);
}
else
{
out.println("<div style='font-size:30px; color:red'>" +"Userid and password does not matched "+"</div>");
RequestDispatcher view =request.getRequestDispatcher("login.html");
view.include(request, response);
}
}
else
{
out.println("<div style='font-size:30px; color:red'>"+"Please fill userid and password"+"</div>");
RequestDispatcher view=request.getRequestDispatcher("login.html");
view.include(request, response);
}
}catch(Exception e){}
finally{
out.close();
}
}
}
注销.java
package servlets;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class logout extends HttpServlet {
/**
*
* @param request
* @param response
* @throws ServletException
* @throws IOException
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
try {
HttpSession session=request.getSession();
session.invalidate();
out.println("<div style='float:left;font-size:25px;'>"+"click here to "
+"<a href='login.html'>login</a></div>");
out.println("<h1 align='center'>"+"Logout Sucessfully..."+"</h1>");
}finally {
out.close();
}
}
}