Menu
I understand the purpose of class annotations, thanks to How and where are Annotations used in Java?. What is the purpose of package annotations, as described in this blog post and §7.4.1 of the Java Language Specification?
Why would you want to associate metadata with a package? What kinds of things could you do?
846
Annotations have a number of uses, among them: Information for the compiler — Annotations can be used by the compiler to detect errors or suppress warnings. Compile-time and deployment-time processing — Software tools can process annotation information to generate code, XML files, and so forth.
Java annotations are metadata (data about data) for our program source code. They provide additional information about the program to the compiler but are not part of the program itself. These annotations do not affect the execution of the compiled program.
Spring Annotations are a form of metadata that provides data about a program. Annotations are used to provide supplemental information about a program. It does not have a direct effect on the operation of the code they annotate. It does not change the action of the compiled program.
Annotation is defined like a ordinary Java interface, but with an '@' preceding the interface keyword (i.e., @interface ). You can declare methods inside an annotation definition (just like declaring abstract method inside an interface). These methods are called elements instead.
74
I suppose @Deprecated would make sense. And maybe something like @Generated if the whole package was generated by some tool from non-Java source. Or @Internal if this package is not part of a public API.
Maybe OSGi tools (where you need to declare the versions of your packages, and the packages you depend on) could make use of this, too.
Has anyone seen those in the wild?
31
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
