java链接mysql, 查询数据库

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

/**
 * 数据库连接
 */
public class DB {
    public static void main(String[] args) {


        //这里我的数据库是task
        String url="jdbc:mysql://localhost:3306/task";
        String user="root";
        String password="951216";
        try {
            Class.forName("com.mysql.jdbc.Driver");
            Connection con = DriverManager.getConnection(url, user, password);
            if (!con.isClosed()) {
                System.out.println("数据库连接成功");
            }
            Statement statement = con.createStatement();
            String sql = "select * from tk_1;";//我的表格叫tk_1
            ResultSet resultSet = statement.executeQuery(sql);
            int id;
            String name;
            int age;
            String school;
           String time;
            while (resultSet.next()) {
                id = resultSet.getInt("id");
                name = resultSet.getString("name");
               age = resultSet.getInt("age");
                school = resultSet.getString("4");
                time = resultSet.getString("time");
                System.out.println("序号:"+id+"  姓名:" + name+"  年龄:"+age+"  学校:  " +school+"  时间:  "+time);
            }
            resultSet.close();
            con.close();
        } catch (ClassNotFoundException e) {
            System.out.println("数据库驱动没有安装");

        } catch (SQLException e) {
            System.out.println("数据库连接失败");
        }
    }
}