protected void init() throws Exception{
gb= new BedReader(file).getGenomicRegionsBuilder();
CrossAnno cr= new CrossAnno(link,0,1);
Iterator<GenomicRegion> it = gb.iterator();
while(it.hasNext()){
GenomicRegion gr= it.next();
String n= gr.attr.toString();
String nn= cr.map(n);
if(nn==null){
nn= n;
}
gr.attr= new Object[]{n, nn};
}