java - Values getting modified in the class during the runtime -

i trying loop around value got populated in registration class. have put breakpoint in getinstance() method in registration class. when cursor reaches below loop code.

for (final registration.holderentry entry : registration.getinstance()) {         // other things.. } 

i f5 on that. , gooes getinstance() method of registration class (below class). , when inspect on instance variable @ point, see values populated in listofbundles list good.

but if keep on pressing f5 again, @ point comes iterator method in registration class , if inspect on listofbundles list, don't see values in list not able understand why happening this. no other code running might change value of listofbundles.

public class registration implements iterable<registration.holderentry> {      private list<string> listofbundles = new linkedlist<string>();     private final map<string, holderentry> bundlemapper = new hashmap<string, holderentry>();       private registration() {         //     }      private static class bundlesholder {         static final registration instance = new registration();     }      public static registration getinstance() {         return bundlesholder.instance;     }         public synchronized void registerbundles(final string bundlename, final ibundlecollection collection) {          holderentry bundleholder = new holderentry(bundlename, collection);          bundlemapper.put(bundlename, bundleholder);         listofbundles.add(bundlename);     }      @override     public synchronized iterator<holderentry> iterator() {          list<string> lst = new linkedlist<string>(listofbundles);         list<holderentry> list = new linkedlist<holderentry>();         (string clname : lst) {             if (bundlemapper.containskey(clname)) {                 list.add(bundlemapper.get(clname));             }         }          collections.reverse(list);         return list.iterator();     }      // other code } 

i hope question clear enough. can tell me wrong going here?

because use static instance return same object from

 public static registration getinstance() 

method. (only 1 time registration initialize).

there no different object iteration. same object iterating on iteration. not applying every object changes make while iterate same object iterate , change values.

i dont know real requirement. try use this.

public static registration getinstance() {         return new registration();;     }