mysql字符集是utf8，eclipse也是utf-8，jdbc也是utf-8,为什么还是乱码？

package com.imooc.jdbc.demo1;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import org.junit.Test;

import com.mysql.jdbc.Driver;

public class JDBCDemo1 {

@Test

/*

* jdbc的入门程序

* */

public void demo1(){

try {

//1.加载驱动

DriverManager.registerDriver(new Driver());

//2.获得链接

Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbctest?characterEncoding=utf-8", "root", "root123");

//3.创建执行SQL语句的对象，并执行SQL

//3.1创建执行SQL的对象

String sql = "select * from user";

Statement stmt = conn.createStatement();

//3.2执行SQL

ResultSet resultSet = stmt.executeQuery(sql);

while(resultSet.next()) {

int uid = resultSet.getInt("uid");

String username = resultSet.getString("username");

String password = resultSet.getString("password");

String name = resultSet.getString("name");

System.out.println(uid+" "+username+" "+password+" "+name);

}

//4.释放资源

resultSet.close();

stmt.close();

conn.close();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}