fam2.add(col3);
builder.addIndexGroup(fam2);
Configuration conf = new Configuration(false);
//convert the map that HTableDescriptor gets into the conf the coprocessor receives
Map<String, String> map = builder.convertToMap();
for(Entry<String, String> entry: map.entrySet()){
conf.set(entry.getKey(), entry.getValue());
}
List<ColumnGroup> columns = CoveredColumnIndexSpecifierBuilder.getColumns(conf);