How should I write my own custom Annotation in Java

Question

Let say I want to check condition[let say boundary values] on some of the method arguments.Instead of writing "if" condition to check [boundary condition] on every method, I want to annotate argument only. Let me know the Steps to understand it. Working code will be awesome.

http://docs.oracle.com/javase/tutorial/java/annotations/. Annotations don't do anything. They just add metadata to the code. You would need a tool, at runtime, to read those annotations and do something with them. — JB Nizet, Mar 14 '15 at 14:58
Might help you http://stackoverflow.com/a/27781761/1697099 and http://stackoverflow.com/a/5686231/1697099 — Premraj, Jul 02 '15 at 13:32

score 1 · Accepted Answer · answered Mar 14 '15 at 15:54

You need to look into method interception. What you are wanting is an interceptor that can validate method arguments on invocation. I like the AOP Alliance interfaces for this, they work pretty well. It also integrates with Guice natively and I think Spring has support for it as well.

Steps:

Define an annotation
Create an interceptor to process the annotation
Bind the interceptor (manually or using some framework)

How should I write my own custom Annotation in Java

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