public static Stats createAndMergeFrom(Stats model){
  Stats r=new Stats(model.name,model.unit,0);
  r.histogram=new int[model.histogram.length];
  System.arraycopy(model.histogram,0,r.histogram,0,model.histogram.length);
  r.counts=new long[model.histogram.length];
  r.merge(model);
  return r;
}

public static Stats createAndMergeFrom ( Stats model ) { Stats r = new Stats ( model . name , model . unit , 0 ) ; r . histogram = new int [ model . histogram . length ] ; System . arraycopy ( model . histogram , 0 , r . histogram , 0 , model . histogram . length ) ; r . counts = new long [ model . histogram . length ] ; r . merge ( model ) ; return r ; }
use this method to merge this stat instance into a prototype one ( for thread safe read only snapshoting )
