code: public static String[] intersect(String[] arr1, String[] arr2) {
  		Map<String, Boolean> map = new HashMap<String, Boolean>();
  		LinkedList<String> list = new LinkedList<String>();
  		for (String str : arr1) {
  			if (!map.containsKey(str)) {
  				map.put(str, Boolean.FALSE);
  			}
  		}
  		for (String str : arr2) {
  			if (map.containsKey(str)) {
  				map.put(str, Boolean.TRUE);
  			}
  		}
  
  		for (Entry<String, Boolean> e : map.entrySet()) {
  			if (e.getValue().equals(Boolean.TRUE)) {
  				list.add(e.getKey());
  			}
  		}
  
  		String[] result = {};
  		return list.toArray(result);
  	}
docs: Arr1 intersect Arr2
  @param arr1
  @param arr2