What is the Java ?: operator called and what does it do?

Question

I have been working with Java a couple of years, but up until recently I haven\'t run across this construct:

int count = isHere ? getHereCount(index) : getAw         


        

Answer 1

You might be interested in a proposal for some new operators that are similar to the conditional operator. The null-safe operators will enable code like this:

String s = mayBeNull?.toString() ?: "null";

It would be especially convenient where auto-unboxing takes place.

Integer ival = ...;  // may be null
int i = ival ?: -1;  // no NPE from unboxing

It has been selected for further consideration under JDK 7's "Project Coin."