How to get the first non-null value in Java?

java coalesce
froadie picture froadie · May 4, 2010 · Viewed 96k times · Source

Is there a Java equivalent of SQL's COALESCE function? That is, is there any way to return the first non-null value of several variables?

e.g.

Double a = null;
Double b = 4.4;
Double c = null;

I want to somehow have a statement that will return the first non-null value of a, b, and c - in this case, it would return b, or 4.4. (Something like the sql method - return COALESCE(a,b,c)). I know that I can do it explicitly with something like:

return a != null ? a : (b != null ? b : c)

But I wondered if there was any built-in, accepted function to accomplish this.

Answer

Andrzej Polis picture Andrzej Polis · Sep 11, 2013

Apache Commons Lang 3

ObjectUtils.firstNonNull(T...)

Java 8 Stream

Stream.of(T...).filter(Objects::nonNull).findFirst().orElse(null)

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