List removes duplicate elements

list:[{"SS": 123, "DD": 234, "DD": 234},{"MM": "FF": oo, "ff": oo}]

This form of:

1List<map<string,object>>NewList2=NewArraylist<map<string,object>>();3Set<set<string>> Keysset =NewHashset<set<string>>();4          for(Map<string, object>map:list) {5set<string> keys =Map.keyset ();6             intBeforesize =keysset.size ();7 keysset.add (keys);8             intAftersize =keysset.size ();9             if(Aftersize = = beforesize + 1){Ten newlist.add (map); One             } A         } - returnNewList;

list:[{groupid=122}, {groupid=124}, {groupid=135}, {groupid=91},

{groupid=109}, {groupid=124}, {groupid=135}, {groupid=126},

{groupid=127}, {groupid=133}, {groupid=134}, {groupid=151}]

This form of:

1List<map<string,object>>NewList2=NewArraylist<map<string,object>>();3Set<map<string,object>>mapset4=NewHashset<map<string,object>>();5          for(Map<string, object>map:list) {6 mapset.add (map);7         }8Iterator<map<string, object>> iteratormap=mapset.iterator ();9     while(Iteratormap.hasnext ()) {Ten Newlist.add (Iteratormap.next ()); One    } A returnNewList;

List removes duplicate elements