/**
 * 定义一个方法，查询emp表的数据将其封装为对象，然后装载集合，返回
 */
public class JdbcDemo06 {
    public static void main(String[]args){
        List<Emp> list = new JdbcDemo06().findall();
        System.out.println(list);
    }
    public List<Emp> findall() {
        Connection conn = null;
        Statement stmt = null;
        ResultSet res = null;
        ArrayList<Emp> list = null;
        try {
            //1.注册驱动
            Class.forName("com.mysql.jdbc.Driver");
            //2.获取连接对象
            conn = DriverManager.getConnection("jdbc:mysql:///db2", "root", "root");
            //3.定义sql
            String sql = "select * from emp";
            //4.获取执行sql对象
            stmt = conn.createStatement();
            //5.执行sql
            res = stmt.executeQuery(sql);
            //6.处理结果
            Emp emp = null;
            list = new ArrayList<>();
            while (res.next()) {
                int id = res.getInt("id");
                String ename = res.getString("ename");
                int job_id = res.getInt("job_id");
                //创建emp对象，并赋值
                emp = new Emp();
                emp.setId(id);
                emp.setEname(ename);
                emp.setJob_id(job_id);
                //装载集合
                list.add(emp);
            }
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        } finally {
            if (stmt != null) {
                try {
                    stmt.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
            if (conn != null) {
                try {
                    conn.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
            if (res != null) {
                try {
                    res.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
        }
    return list;
    }
}
输出结果为：
    [Emp{id=1001, ename='孙悟空', job_id=4}, Emp{id=1002, ename='卢俊义', job_id=3}, Emp{id=1003, ename='林冲', job_id=3}, Emp{id=1004, ename='唐僧', job_id=2}, Emp{id=1005, ename='李逵', job_id=4}, Emp{id=1006, ename='宋江', job_id=2}, Emp{id=1007, ename='刘备', job_id=2}, Emp{id=1008, ename='猪八戒', job_id=4}, Emp{id=1009, ename='罗贯中', job_id=1}, Emp{id=1010, ename='吴用', job_id=3}, Emp{id=1011, ename='沙僧', job_id=4}, Emp{id=1012, ename='李逵', job_id=4}, Emp{id=1013, ename='小白龙', job_id=4}, Emp{id=1014, ename='关羽', job_id=4}]