servlet代码:添加用户

servlet代码:添加用户

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

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

public class qqq extends HttpServlet {

private Connection conn; //初始化连接
private Statement stmt; //初始化数据库操作
ResultSet rs=null; //初始化结果集

public qqq() {
super();
}

public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

response.setContentType("text/html");
PrintWriter out = response.getWriter();
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/user?user=root&password=root");
stmt = conn.createStatement();

String username = request.getParameter("username");
String password = request.getParameter("password");
rs = stmt.executeQuery("SELECt * FROM user where username="+username);
if(rs.next()){out.println("用户名已存在");}
else{stmt.execute("insert into user values("+username+","+password+");");}
conn.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

out.println("");

}

public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

response.setContentType("text/html");
PrintWriter out = response.getWriter();
out
.println("");
out.println("");
out.println(" ");
out.println(" ");
out.print(" This is ");
out.print(this.getClass());
out.println(", using the POST method");
out.println(" ");
out.println("");
out.flush();
out.close();
}

}

可以在你的方法里面使用httpservletresponse对象的sendredirect方法，这个是用来重定向的！比如在doget方法里面 servletsample.java   import java.io.*;   import java.util.*;   import javax.servlet.*;   import javax.servlet.http.*;    public class servletsample extends httpservlet   {    //第一步：扩展httpservlet抽象类   public void doget(httpservletrequest request,httpservletresponse response) throws servletexception,ioexception   {    response.sendredirect(" http://www.realsung.com");.//这个是重定向到其他网站的 }   }