使用JDBC连接mysql数据库

packageblog.dao.impl;

importjava.sql.Connection;
importjava.sql.DriverManager;
importjava.sql.PreparedStatement;
importjava.sql.ResultSet;
importjava.sql.SQLException;
importjava.sql.Statement;
importjava.util.ArrayList;
importjava.util.List;

importorg.apache.log4j.Logger;

importblog.dao.UserDao;
importblog.domain.DeptBean;
importblog.domain.UserBean;
importblog.exception.UserException;

publicclass UserdaoImpl implements UserDao{

privatestatic final Logger log = Logger.getLogger(UserdaoImpl.class);

@Override
publicUserBean login(String username, String pwd) throwsUserException {
//使用JDBC操作数据
Connection conn =null;
Statement stmt =null;
ResultSet rs =null;
//1、首先注册具体数据库的驱动包

try{

Class.forName("com.mysql.jdbc.Driver");

//2、利用DriverManager获取数据库连接对象Connection
String url ="jdbc:mysql://localhost:3306/pmdb?useUnicode=true&characterEncoding=utf-8";
String us ="root";
String password ="1234";
conn = DriverManager.getConnection(url, us, password);

//3、创建语句对象
stmt = conn.createStatement();

//4、执行SQL操作，返回结果集ResultSet
String sql ="select * from t_user where fusername='" + username + "' and fpassword='" + pwd + "'";
rs = stmt.executeQuery(sql);

//5、访问结果集对象，取出每个字段的值
if(rs.next()){

UserBean userBean =new UserBean();
userBean.setUid(rs.getInt("fuid"));
userBean.setFullname(rs.getString("ffullname"));
userBean.setUsername(rs.getString("fusername"));
userBean.setPassword(rs.getString("fpassword"));
userBean.setMobile(rs.getString("fmobile"));
userBean.setTel(rs.getString("ftel"));
userBean.setEmail(rs.getString("femail"));
userBean.setTitle(rs.getString("ftitle"));
returnuserBean;
}
}catch (ClassNotFoundException e) {
thrownew UserException("用户登陆验证失败");

}catch (SQLException e) {
thrownew UserException("用户登陆验证失败");

}finally{
try{
////6. 关闭数据库资源，关闭的顺序与申明的顺序相反
if(rs!=null)rs.close();
if(stmt!=null)stmt.close();
if(conn!=null)conn.close();
}catch (SQLException e) {
thrownew UserException("用户登陆验证失败");
}
}
returnnull;
//如果出现了任何错误，return userBean 不会被执行，执行return null,也就是返回空
}

}