java - TreeSet Comparator -

i have treeset , custom comparator. values server according changes in stock

ex: if time=0 server send entries on stock (unsorted) if time=200 server send entries added or deleted after time 200(unsorted)

in client side sorting entries. question more efficient

1> fetch entries first , call addall method or 2> add 1 one

there can millions of entries.

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  private static map<integer, keywordinfo> hashmap = new hashmap<integer, keywordinfo>();   private static set<integer> sortedset = new treeset<integer>(comparator);        private static final comparator<integer> comparator = new comparator<integer>() {         public int compare(integer o1, integer o2) {           int integercomparevalue = o1.compareto(o2);           if (integercomparevalue == 0) return integercomparevalue;           keywordinfo k1 = hashmap.get(o1);           keywordinfo k2 = hashmap.get(o2);           if (null == k1.getkeyword()) {             if (null == k2.getkeyword())               return integercomparevalue;             else               return -1;           } else {             if (null == k2.getkeyword())               return 1;             else {               int comparestring = alphanumericcmp.comparator.compare(k1.getkeyword().tolowercase(), k2.getkeyword().tolowercase());               //int comparestring =  k1.getkeyword().compareto(k2.getkeyword());               if (comparestring == 0)                 return integercomparevalue;               return comparestring;             }           }         }       }; 

now there event handler gives me arraylist of updated entries, after adding them hashmap calling

final map<integer, keywordinfo> maptoreturn = new submap<integer, keywordinfo>(sortedset, hashmap); 

i think bottleneck can more network-related cpu related. bulk operation fetching new entries @ once more network efficient.

with regards cpu, time required populate treeset not change consistently between multiple add()s , addall(). reason behind treeset relies on abstractcollection's addall() (http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/6-b27/java/util/abstractcollection.java#abstractcollection.addall%28java.util.collection%29) in turn creates iterator , calls multiple times add().

so, advice on cpu side is: choose way keeps code cleaner , more readable. obtained through addall().