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What is the need for a collection structure in java?

What is the need for a Java collection structure, since all data operations (sorting / adding / deleting) are possible using arrays, and in addition, the array is suitable for memory consumption, and performance is also better than collections.

Can someone point me to a real-time data-oriented example that shows the difference in both (array / collections) of these implementations.

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10 answers
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To learn more about Java collections, check out this article .

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