What's the point in Lombok annotation @NonNull for a method?
class MyClass {
    @NonNull
    void run() {
        // code here
    }
}
Are we check the instance of class MyClass (MyClass obj == null)?
 
  
                     
                        
For a void method, there's no point.
For a method with a return type, it shows that it won't return null:
@NonNull String foo() {
    // I promise I won't return null herre!
}
Judging by the tutorial, it looks like it won't generate a check within the method to ensure that it isn't null, but it tells any caller that they can realistically expect a non-null value to be returned.
 
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