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How to use Collections.binarySearch for ArrayList<List> arr in java

I have an ArrayList<List<String>> and im trying to use the built-in binary search in the collection but I always come up with an error

int index = Collections.binarySearch(arraylistdata, id);

Where arraylistdata is my ArrayList of List<String>.

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Answer

JavaScript

This works fine, but you need to known that Collections#binarySearch accept a List<? extends Comparable<? super T>> as its first parameter.

While in your case, ArrayList<List<String>> does not match the requirement , as List<String> or List<?> itself is not a Comparable object.

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