Converting ArrayList to Set in Java means creating a Set implementation like HashSet from an ArrayList full of objects.Before Converting your ArrayList into hashSet do remember that List keep insertion order and guarantees same but Set doesn't have such obligation. Also List allows duplicates but Set doesn't allow any duplicates, which means if you have duplicates in your ArrayList they will be lost when you convert ArrayList to HashSet and that's the reason why sometime size of ArrayList doesn't match with size of HashSet after conversion. Converting ArrayList to Set is entirely different than Converting Map to List but has one thing common , A constructor which takes a collection object. HashSet also has a constructor which takes another collection object e.g. ArrayList and creates Set out of those element. we have also seen a bit of this on 10 Examples of ArrayList in Java and we will see here in detail.
Sabtu, 07 Januari 2012
core java
How to convert ArrayList to Set in Java with Example
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Nice article . Keep this work up. There is good hashset example visit Hashset in java
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