}
public void testSecondaryTreeMapManyToOne() throws IOException{
RecordManager r = newRecordManager();
PrimaryTreeMap<Integer, String> m = r.treeMap("aa");
SecondaryTreeMap<Integer, Integer, String> s = m.secondaryTreeMapManyToOne("bb",
new SecondaryKeyExtractor<Iterable<Integer>, Integer, String>() {
public List<Integer> extractSecondaryKey(Integer key, String value) {
return list(value.length(),10+value.length());