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Get Duplicate Objects from an ArrayList of Objects

 
Greenhorn
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How can I get duplicates Objects from an ArrayList?


 
Bartender
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A probably faster way is to use the containsAll() method but this method returns a boolean rather than a collection.

For non-duplicate Set works perfectly fine. You can do new HashSet<Order>(originalOrderList) instead of looping and checking.

 
Rancher
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Goutam reddy wrote:How can I get duplicates Objects from an ArrayList?


Without overriding the equals() and hashCode() methods in your Order class, the only time you will get a duplicate is if you are comparing an object with itself.
See the descriptions of those methods here for more details.
 
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