Java Skip null object when returning with .equals()

Question

I am trying out some code optimization and my current unique title validation for an object looks like this:

public boolean validateTitle(RawProfileConstraint rawProfileConstraint) {
    RawProfileConstraint result = profileConstraintMapper.validateTitle(rawProfileConstraint.getTitle());
    return (!rawProfileConstraint.getTitle().equals(result.getTitle()));
}

This works, until it throws a tantrum where the database is unable to retrieve a record that contains the title that I'm trying to validate - a.k.a it is available. result will be null in that case. How can I incorporate a handler for null in this case scenario without your usual if-else?

Answer 1

Simply check if result is null before dereferencing it:

return result != null
    && !rawProfileConstraint.getTitle().equals(result.getTitle());

or

return result == null
    || !rawProfileConstraint.getTitle().equals(result.getTitle());

depending upon what you want the result to be when result == null (false and true respectively).

&& and || short-circuit, so they won't evaluate the right-hand operand unless necessary:

• false && anything == false, so there's no need to evaluate anything
• true || anything == true, so there's no need to evaluate anything

Answer 2

One option to avoid checking for null is to use an Optional (if you are using Java 8) :

Replace

result.getTitle()

with

Optional.ofNullable(result).map(RawProfileConstraint::getTitle).orElse("")