FULL PRODUCT VERSION :
java version "1.8.0_111"
Java(TM) SE Runtime Environment (build 1.8.0_111-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux y700 4.8.0-32-generic #34-Ubuntu SMP Tue Dec 13 14:30:43 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux


A DESCRIPTION OF THE PROBLEM :
Creating stream of random value from java.util.Random class returns unsized stream.

As result count() operation on large sets of data take a long time, using parallel streams give no performance improvemn due to bad splitting streams.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
DoubleStream doubles = random.doubles(SIZE, 0, 1);

doubles.count() <- TAKE A LONG TIME TO EXECUTE
doubles.parallel.count() <- gives no benefits



EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
stream size is known and flag should be present
but double pipeline doesn't rely on size flag

public final long count() {
        return mapToLong(e -> 1L).sum();
}
ACTUAL -
for sized stream count could return size immediately

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
DoubleStream doubles = random.doubles(SIZE, 0, 1);
double count = doubles.count();
 
---------- END SOURCE ----------