package myweb2;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.ResultSet;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//import com.mysql.jdbc.Connection;
import java.sql.Connection;
import com.mysql.jdbc.PreparedStatement;
public class LoginServlet extends HttpServlet {
/**
* Constructor of the object.
*/
public LoginServlet() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @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 doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String username=request.getParameter("username");
String password=request.getParameter("password");
if(username==null||username.equals("")||password==null||password.equals("")){
System.out.println("您输入的用户名和密码有误");
return;
}
DBManager dbmanager=null;
try {
Connection conn = dbmanager.getConn();
PreparedStatement pst=(PreparedStatement) conn.prepareStatement("select * from mytable where username=? AND password=?");
pst.setString(1,username);
pst.setString(2,password);
ResultSet rs=pst.executeQuery();
if (rs.next()){
System.out.println("访问成功");
} else { System.out.println("访问失败 ");}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally{
conn.close();
};
if(username=="woniu"&&password=="123456"){
}
}
问题: conn.close(); 老是报错,提示有问题,关不不来,是怎么回事啊,那个大神给看看啊