一个简单的登陆例子

package com.conn;
import java.sql.*;
public class Login {
 public int isLogin(String name,String pwd){
        int flag=0;
        Connection conn=null;
        PreparedStatement pst=null;
        ResultSet rs=null;
      //加载驱动
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException ex) {
            ex.printStackTrace();
        }
        //连接数据库
        try {
            conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/Psychology","root","123456");
            String sql="select * from users where username=? and userpassword=?";
            pst=conn.prepareStatement(sql);
            pst.setString(1,name);
            pst.setString(2,pwd);
            rs=pst.executeQuery();
            if(rs.next())
                flag=1;
        } catch (Exception ex) {
            ex.printStackTrace();
        }finally{
            try {
                conn.close();
            } catch (Exception ex) {
                ex.printStackTrace();
            }
        }
        return flag;

    }

}