1.创建web工程
2.导入mysql驱动
3.创建servlet
package com.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
public class RegistServlet extends HttpServlet {
private Connection con=null;
private PreparedStatement pstmt=null;
private ResultSet rs;
private HttpSession session;
public RegistServlet() {
super();
}
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
public void doDelete(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
// Put your code here
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the GET method");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String username=request.getParameter("username");
String password=request.getParameter("password");
session=request.getSession();
try {
String sql="SELECT * FROM admin WHERE username=?";
con=ConnectionManage.getConnection();
pstmt=con.prepareStatement(sql);
pstmt.setString(1, username);
rs=pstmt.executeQuery();
if(rs.next()){
request.getRequestDispatcher("/index.jsp").forward(request, response);
}else{
String sql2="insert into admin values(?,?)";
pstmt=con.prepareStatement(sql2);
pstmt.setString(1, username);
pstmt.setString(2, password);
int success=pstmt.executeUpdate();
request.getRequestDispatcher("/success.jsp").forward(request, response);
session.setAttribute("message", "注册成功");
}
} catch (SQLException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
public void init() throws ServletException {
// Put your code here
}
}
4.注册页面：略
总结:要想在session中设置属性，在servlet不能直接获得Httpsession对象，而是通过request对象的getSession()方法