A "NullPointerException" could be thrown; "entity" is nullable here

Question

I get an error A "NullPointerException" could be thrown; "entity" is nullable here. below is a sample of my code.

NewResponse newResponse = new NewResponse();
if(entity.getName() != null){
        GetDetails response = crossService
            .getDetails(entity.getName());

        response.setHumanName(response.getFullName());
        }

Is there a way that I can fix null pointer dereference?

Check whether `entity` is null before calling `entity.getName()`. — Robby Cornelissen, Sep 28 '18 at 06:39
entity.getName() is nullable. that's why I get this kind of error. But I already set a condition to (entity.getName != null) — newbie, Sep 28 '18 at 06:40
entity.getName() is nullable. how should it be coded so that it will not return NPE? — newbie, Sep 28 '18 at 06:41
@newbie the first comment answers your question: Check whether entity is null before calling entity.getName() — JB Nizet, Sep 28 '18 at 06:42

score -1 · Answer 1 · edited Sep 28 '18 at 07:14

Firstly, the entity object can be null. You are not doing any null check for entity. You can do that by if(null! =entity). Secondly, you are doing entity.get operations, this operation can throw a null pointer exception as well. Thus we need a null check here as well. So conbined together you can do like

if (null! =entity && null! = entity.getName()) {

//Do your stuff here.

}

By doing this check you will not get a null pointer warning as well as null pointer exception. Alternatively uf you are using java 8 then you can use an "optional" for the same. Which is a more cleaner way for avoiding null pointers.

A "NullPointerException" could be thrown; "entity" is nullable here

1 Answers1