运行之后没反应

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;
 
public class JDBCDome1 {
     
    @Test
    /**
     * JDBC的入门程序
     */
    public void demo1(){
        Connection conn = null;
        Statement stmt = null;
        ResultSet rs = null;
         
        // 1.加载驱动
        try {
            Class.forName("com.mysql.cj.jdbc.Driver");
            // 2.获得连接
            conn = DriverManager.getConnection(
                    "jdbc:mysql://127.0.0.1:3306/jdbctest"
                    +"?useSSL=false&serverTimezone=Hongkong&useUnicode=true&characterEncoding=utf-8",
                    "root","980326");
            // 3.创建执行sql语句的对象，并且执行sql
            // 3.1  创建执行sql的对象
            String sql = "select * from user";
            stmt = conn.createStatement();
            // 3.2  执行sql语句
            rs = stmt.executeQuery(sql);
            while(rs.next()){
                int uid = rs.getInt("uid");
                String username = rs.getString("username");
                String password = rs.getString("password");
                String name = rs.getString("name");
                 
                System.out.println(uid+"   "+username+"   "+password+"   "+name);
            }
            // 4.释放资源
            rs.close();
            stmt.close();
            conn.close();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}