如何获取一个java类中的属性数？ [英] How to get number of attributes in a java class?

问题描述

我有一个包含数据库表所有列的java类作为属性（成员变量）和相应的getter和setter。

I have a java class containing all the columns of a database table as attributes (member variables) and corresponding getters and setters.

我想有一个方法这个类叫做 getColumnCount（），返回列数（即类中的属性数）？我怎么实现这个没有硬编码的数字？我对这一般的建议和建议开放。感谢。

I want to have a method in this class called getColumnCount() that returns the number of columns (i.e. the number of attributes in the class)? How would I implement this without hardcoding the number? I am open to critisims on this in general and suggestions. Thanks.

推荐答案

检查 reflection API 。如果相关类别实际上是一个纯 Javabean，则可以按如下方式获取字段数（属性或列）：

Check the reflection API. If the class in question is actually a pure Javabean, you can get the number of fields (properties or columns as you call it) as follows:

public int getColumnCount() {
    return getClass().getDeclaredFields().length;
}

我非常怀疑这一点的需要。如果你详细说明你认为你需要这种方法/解决方案的功能需求，那么我们可以建议更好的方法。

I however highly question the need for this. If you elaborate a bit more about the functional requirement for which you think that you need this approach/solution, then we may be able to suggest better ways.

这篇关于如何获取一个java类中的属性数？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！