How to Retain the Insertion Order in a Map

Use LinkedHashMap to retain

Map map = new LinkedHashMap();
// Add some elements
map.put("a", new Integer(1));
map.put("b", new Integer(2));
map.put("c", new Integer(3));

// List the entries
for (Iterator it=map.keySet().iterator(); it.hasNext(); ) {
Object key = it.next();
Object value = map.get(key);
}
// [a=1, b=2, c=3]