RFR 9: 8138963 : java.lang.Objects new method to default to non-null

[Roger Riggs]

Hi Stephen,

Guava's firstNonNull is a useful semantic, but would not be a drop in 
replacement for existing code which
would need to be examined for behavioral changes due to possibly 
throwing an exception.
So perhaps the nonNullorElse name would be more accurate.

Thanks, Roger


On 10/6/2015 10:00 AM, Stephen Colebourne wrote:
> Guava uses firstNonNull(a, b). It ensures that the result is never
> null, by checking that b is not null.
> I think the semantics of Guava's method is correct. I tend to think
> the method name isn't bad either.
>
> Calling it nonNull(Object,Object) clashes with the existing
> nonNull(Object) method. Those two have nothing much to do with each
> other.
>
> Stephen
>
>
> On 6 October 2015 at 14:43, Roger Riggs <Roger.Riggs at oracle.com> wrote:
>> Java.lang.Objects contains a number of convenience methods to make it easier
>> to handle references that are null.
>> For example, toString(obj, nullDefault),
>>
>> A new method is proposed to return the reference or a default value if the
>> reference is null.
>>     static <T> T nonNull(T obj, T nullDefault);
>>
>> Alternatives to the method name include
>> nonNullOrElse ( using the java.util.Optional name pattern) or
>> nonNullOrDefault
>>
>> Please review and comment.
>>
>> Webrev:
>>    http://cr.openjdk.java.net/~rriggs/webrev-object-non-null/
>>
>> Issue:
>>    https://bugs.openjdk.java.net/browse/JDK-8138963
>>
>> Thanks, Roger
>>