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Save Article. Improve Article. Like Article. Since static. Output: From parent static m1 From child non-static instance m2. Previous Different ways of Method Overloading in Java. Recommended Articles. Article Contributed By :. Easy Normal Medium Hard Expert. Than can help in debugging. Also, in Joshua Block's book Effective Java 2nd edition , item 36 gives more details on the benefits of the annotation. It makes absolutely no sense to use Override when implementing an interface method.
There's no advantage to using it in that case--the compiler will already catch your mistake, so it's just unnecessary clutter. The Override annotation assures you that you did in fact override something. Without the annotation you risk a misspelling or a difference in parameter types and number. I use it every time. It's more information that I can use to quickly figure out what is going on when I revisit the code in a year and I've forgotten what I was thinking the first time.
Override usefulness is to detect changes in parent classes which has not been reported down the hierarchy. Without it, you can change a method signature and forget to alter its overrides, with Override, the compiler will catch it for you. I use it everywhere.
On the topic of the effort for marking methods, I let Eclipse do it for me so, it's no additional effort. I'm religious about continuous refactoring Be careful when you use Override, because you can't do reverse engineer in starUML afterwards; make the uml first. It seems that the wisdom here is changing. Today I installed IntelliJ IDEA 9 and noticed that its " missing Override inspection " now catches not just implemented abstract methods, but implemented interface methods as well.
In my employer's code base and in my own projects, I've long had the habit to only use Override for the former -- implemented abstract methods. However, rethinking the habit, the merit of using the annotations in both cases becomes clear. Of course, this scenario is mostly hyperbole; the derived class would no longer compile, now lacking an implementation of the renamed interface method, and today one would likely use a Rename Method refactoring operation to address the entire code base en masse.
Given that IDEA's inspection is not configurable to ignore implemented interface methods, today I'll change both my habit and my team's code review criteria. The annotation Override is used for helping to check whether the developer what to override the correct method in the parent class or interface.
When the name of super's methods changing, the compiler can notify that case, which is only for keep consistency with the super and the subclass. BTW, if we didn't announce the annotation Override in the subclass, but we do override some methods of the super, then the function can work as that one with the Override. But this method can not notify the developer when the super's method was changed.
Because it did not know the developer's purpose -- override super's method or define a new method? So when we want to override that method to make use of the Polymorphism, we have better to add Override above the method.
I use it as much as can to identify when a method is being overriden. If you look at the Scala programming language, they also have an override keyword. I find it useful. It does allow you well, the compiler to catch when you've used the wrong spelling on a method name you are overriding.
Override annotation is used to take advantage of the compiler, for checking whether you actually are overriding a method from parent class.
It is used to notify if you make any mistake like mistake of misspelling a method name, mistake of not correctly matching the parameters. Annotations do provide meta data about the code to the Compiler and the annotation Override is used in case of inheritance when we are overriding any method of base class.
It just tells the compiler that you are overriding method. It can avoide some kinds common mistakes we can do like not following the proper signature of the method or mispelling in name of the method etc. So its a good practice to use Override annotation. For me the Override ensures me I have the signature of the method correct.
If I put in the annotation and the method is not correctly spelled, then the compiler complains letting me know something is wrong. Simple—when you want to override a method present in your superclass, use Override annotation to make a correct override. The compiler will warn you if you don't override it correctly. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow.
Learn more. When do you use Java's Override annotation and why? Ask Question. Asked 13 years, 1 month ago. Active 9 years, 2 months ago. Viewed k times. Greg Mattes 31k 14 14 gold badges 67 67 silver badges bronze badges. Alex B Alex B Active Oldest Votes. Dave L. Along the same lines as "easier to understand", the IDEs will spot the Override annotation and visually flag the overriding method in the editor.
Some IDEs will flag an overridden method that is missing the Override annotation as well. The other benefit is that if the parent class changes, the compiler will make sure that the child classes have been updated as well. Jay R. As a matter of fact, e. Eclipse can even automatically add the Override if it is missing. In case anyone else got here because of the apparently undocumented change from 1.
Thanks for pointing it out, Dave L.! Show 5 more comments. Documented Documented annotation indicates that whenever the specified annotation is used those elements should be documented using the Javadoc tool. By default, annotations are not included in Javadoc. For more information, see the Javadoc tools page. Target Target annotation marks another annotation to restrict what kind of Java elements the annotation can be applied to. A target annotation specifies one of the following element types as its value:.
Inherited Inherited annotation indicates that the annotation type can be inherited from the super class. This is not true by default. When the user queries the annotation type and the class has no annotation for this type, the class' superclass is queried for the annotation type.
This annotation applies only to class declarations. Repeatable Repeatable annotation, introduced in Java SE 8, indicates that the marked annotation can be applied more than once to the same declaration or type use. For more information, see Repeating Annotations. All rights reserved. Hide TOC.
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