DBUtils查找最大的ID总是返回0

1.实体:

public class Order {
    private int id;
    private Date orderDate;
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public Date getOrderDate() {
        return orderDate;
    }
    public void setOrderDate(Date orderDate) {
        this.orderDate = orderDate;
    }
    @Override
    public String toString() {
        return "Order [id=" + id + "]";
    }
    public Order() {
        super();
    }
}

 

2.dao查找最大的ID

private static final Class CLAZZ = Order.class;
public Object findMaxID() {
        String sql = "select max(id) from tb_order";
        Object[] params = null;
        return super.find(sql, CLAZZ, params);
    }

 

3.返回值总是0

 

4.SQL语句改成:

String sql = "select max(id) as id from tb_order";

 

5.最后实体Order中的id能获得最大的值