CODEWITHSUNDEEP
java
Pan Bydlak
Pan Bydlak

Reputation: 567

How to make @NotNull throw runtime exception?

Is there any framework that can throw exception if I pass null as parameter to @NotNull annotation? I don't mean static analysis but run-time checks.

If not, how to implement it?

Upvotes: 4

Views: 5785

Answers (2)

Kelvin Ng
Kelvin Ng

Reputation: 174

Lombok @NonNull generates those boilerplate for you. Instead of annotating method with @NotNull, you annotate the parameter @NonNull instead.

import lombok.NonNull;

public class NonNullExample extends Something {
   private String name;
   public NonNullExample(@NonNull Person person) {
       super("Hello");
////   if (person == null) {
////       throw new NullPointerException("person");
////   }
       this.name = person.getName();
   }
}

See the many questions tagged to learn more.

Upvotes: 4

Sleiman Jneidi
Sleiman Jneidi

Reputation: 23329

If you are using Java 6 or a lower version then you can use Guava Preconditions.

Preconditions.checkNotNull(param);

However, if you using Java 7 or a higher version then there is a Utility method in Objects.

 Objects.requireNonNull(param);

And there is an overload that takes string to add a message to the NullPointerException that will be thrown 

Objects.requireNonNull(param,"Param cannot be null");

Upvotes: 7

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