Or do you mean that if LinkedHashMap is used the output will be name1#name2#name3#name4 always.
Reading the JavaDoc should *always* be done first !! This is from the first paragraph of the JavaDoc for the LinkedHashMap.
public class LinkedHashMap
extends HashMap
Hash table and linked list implementation of the Map interface, with predictable iteration order. This implementation differs from HashMap in that it maintains a doubly-linked list running through all of its entries. This linked list defines the iteration ordering, which is normally the order in which keys were inserted into the map (insertion-order). Note that insertion order is not affected if a key is re-inserted into the map. (A key k is reinserted into a map m if m.put(k, v) is invoked when m.containsKey(k) would return true immediately prior to the invocation.)
Henry