@Foos({ @Foo(0),@Foo(1),@Foo(2) })
public void bar() {}
由于我使用{…}初始化程序创建了一个数组,所以当我稍后通过Reflection访问此方法时,顺序与声明的相同是非常清楚的.
但是,当我使用Java 8中的新@Repeatable注释时,我是否保证将保留订单？
我宣布了一组简单的注释：
public @interface Foos {
Foo[] value();
}
@Repeatable(Foos.class)
public @interface Foo {
int value();
}
并针对最多样化的场景运行一些测试：
@Foo(0) @Foo(1) @Foo(2)
public void bar1() {}
@Foo(2)
@Deprecated @Foo(5)
@Foo(10)
public void bar2() {}
一切似乎完美无缺(当通过Reflection访问时),但我不想依赖于未记录的东西.我觉得应该是这样,但我无法在任何地方找到它！任何人都可以对此有所了解吗？
解决方法
If a declaration context or type context has multiple annotations of a repeatable annotation type T,then it is as if the context has no explicitly declared annotations of type T and one implicitly declared annotation of the containing annotation type of T.
The implicitly declared annotation is called the container annotation,and the multiple annotations of type T which appeared in the context are called the base annotations. The elements of the (array-typed) value element of the container annotation are all the base annotations in the left-to-right order in which they appeared in the context.
(强调我的)
所以,是的,容器注释中的注释顺序与可重复注释的声明顺序相同.