How to get unique values from two Collection objects in JAVA
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I would like to get Unique values from two collection objects. How to get it? 
Example: Let us take two ArrayLists (Collection Object)

List bag1 = new ArrayList(); 
List bag2 = new ArrayList();

bag1.add("1"); bag1.add("2"); bag1.add("3"); bag1.add("7"); bag1.add("8"); bag1.add("9");
bag2.add("4"); bag2.add("5"); bag2.add("6"); bag2.add("7"); bag2.add("8"); bag2.add("9");

I need to get Result like --> 1,2,3 from Bag1 and 4,5,6 from Bag2

Could you please help me out?

Tx - 
Sriks