请问这是怎么回事

package com.imooc.jdbc.demo1;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

import java.sql.Statement;

import org.junit.Test;

public class JDBCDemo2 {

@Test

public void demo2() {

Connection conn=null;

Statement stmt=null;

try {

//1.注册驱动

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

//2.获得连接

conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbctest", "root", "abc123");

//3.获得执行SQL语句的对象，并且执行SQL

stmt=conn.createStatement();

//3.1编写SQL

String sql="insert into user values(null,'eee','123','张三')";

//3.2执行SQL

int i=stmt.executeUpdate(sql);

if(i>0) {

System.out.println("执行成功");

}

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}finally{

//4.释放资源

if(stmt!=null) {

try {

stmt.close();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

stmt=null;

}

if(conn!=null) {

try {

conn.close();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

conn=null;

}

}

}

}

eclipse第一次用的是gbk格式，后面发现有问号，改成utf8模式，发现名字栏还是问号