Why does the Java Collections Framework offer two different ways to sort?

Question

If I have a list of elements I would like to sort, Java offers two ways to go about this.

For example, lets say I have a list of Movie objects and I’d like to sort

Answer 1

One is for conciseness for what should be a common case (Effective Java 2nd Edition, Item 12: Consider implementing Comparable). The other, as you noted, is for flexibility and general-purposeness.

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