technique from tremendous class
or interface.
Although it might look trivial @Override is especially helpful whereas overriding strategies that settle for Object as a parameter similar to equals,
compareTo
or examine() technique of Comparator interface. @Override is without doubt one of the three built-in annotations offered by
Java 1.5, the opposite two are @SuppressWarnings and @Deprecated.
normal nature, whereas @SuppressWarnings can be used whereas utilizing Generics, @Deprecated is
largely for API and library.
If in case you have learn my article frequent
errors whereas overriding equals technique then you have got seen that one of many
mistake Java programmer makes it, write equals technique with non-object argument sort as
proven within the beneath instance:
public class Particular person{
non-public String
identify;
public boolean equals(Particular person
particular person){
return
identify.equals(particular person.identify);
}
}
right here programmer is trying to override equals() technique, however as a substitute of overriding, its a overloaded
technique. This error silently escape from compiler and never even floor on
runtime by any Exception and it’s very laborious to detect. @Override
annotation in Java prevents this class of mistake.
In the event you put @Override
annotation above equals technique than compiler will confirm if this technique really overrides a brilliant class or interface technique or
not. if its not then it throw compilation error like “technique doesn’t
override or implement a technique from a brilliant sort.
In brief @Override
annotation saves numerous debugging effort by avoiding this extreme mistake
in Java. This single cause is sufficient to persuade programmers to at all times use @Override
annotation whereas implementing tremendous sort strategies.
I will provide you with another instance, the place @Override annotation has saved me numerous instances. Generally I make errors like, overriding technique with out argument, which suggests, I intend to override a technique, which takes an argument and finally ends up writing a brand new technique with the identical identify with out argument.
This turns into actually nasty, particularly if the unique technique is just not summary, as a result of then the compiler won’t present any warning or error. However if you’re utilizing @Override annotation, the Compiler will warn you with an error that it really doesn’t override tremendous class technique.
may also be utilized by IDE and static code analyzer to counsel a default
implementation or coding
greatest practices.
@Override annotation in Java with Instance
One of many main issues with @Override annotationon JDK 1.5 was that it will probably solely be used along with tremendous class
i.e. compiler throws an error in the event you use @Override annotation
with interface
technique.
From Java 6 onwards you need to use @Override annotation
whereas implementing the interface technique as nicely. This supplies strong compile-time checking
of overriding. If in case you have been utilizing Eclipse
IDE then you should have confronted difficulty together with @Override annotation
the place compiler complains even in the event you override interface technique and solely repair was
both take away all @Override annotation from the interface technique
or shift to Java supply 1.6 from compiler settings.
It’s best to at all times use @Override annotation at any time when utility, that is even prompt by Google’s Java greatest follow information as nicely. @Override is authorized within the following circumstances :
- When a category technique is overriding a super-class technique.
- When a category technique is implementing an interface technique.
- When an interface technique re specifying a super-interface technique.
The one place, the place you do not need to use @Override is when the dad or mum technique is @Deprecated.
That is all on @Override annotation in Java. It is one in all
the most effective Java coding follow to make use of @Override annotation
whereas overriding any technique from superclass or interface. This may prevent from making errors that are laborious to seek out and debug with a stay utility.
This annotation has saved many errors throughout compile time from each junior and senior builders a like. Now days, IDE will mechanically put the override annotation for you everytime you override a superclass technique in Java.
Different Java greatest practices tutorial from Javarevisited Weblog
