public static int getBegin(int interval) {
        return interval >>> 16;
    }
Utility class for interval related constants and methods.
An interval consists of a begin and end value indicating the start and end of the interval.
Both value are inclusive, eg (1,2) is an interval of size 2.

There are 3 types of interval; normal, ZStar1 and ZStar2.

Normal intervals have begin value in 16 MSB and end in 16 LSB.
ZStar1 intervals have end value in 16 MSB and begin in 16 LSB.
ZStar2 intervals have only an end value located at 16 LSB.

@author Magnar Nedland
@author bjorncs
predicate-search/src/main/java/com/yahoo/search/predicate/index/Interval.java