One factor to keep in mind when working with annotations is that the named values must always be compile-time constants and can never be null.

使用注释时要记住的一个因素是，命名值必须始终是编译时常量，而且不能为null。

youdao

This is great when it occurs, but it doesn't help very often because it's much more common to build strings from runtime data than from compile-time constants.

这种功能非常了不起，但它并不经常起作用，因为通常从运行期数据创建字符串而不是从编译期常量。

youdao

Constants are fields or properties whose value is set at compile time and cannot be changed.

常量是在编译时设置其值并且不能更改其值的字段或属性。

youdao