Jonathan Pitre Jonathan Pitre - 3 months ago 7
Java Question

Can constructor return a null object?

While looking through some old code I came across this gem:

MyObject o = new MyObject("parameter");
if (o == null) o = new MyObject("fallback parameter");


The second line is marked in Eclipse as dead code, and I understand why. No exception seems to be explicitly thrown, and it isn't possible for the
MyObject
constructor to throw any kind of exception (such as
NullPointerException
s).

My question is why there is a null check? Was it previously possible in an old version of Java for a constructor to return null? Or is this simply useless and dead code?

Answer

The code is dead in any version of java. It's not possible for a constructor to return null and even if an exception would be thrown from the constructor, the next line won't be called.

Comments