java - How to sort dates in a List -

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java - How to sort dates in a List -

how can sort dates within list?

i have read can achieved using treemap, sorted , navigable map organizes elements in self-balancing binary tree. expensive.

my question - best , efficient way accomplish result?

it depends. if want have "always sorted" container treeset friend. adding element treemap o(log(n)) - (very good, faster linear).

if need sort 1 time (no adding elements later), set arraylist , utilize sort() method. optimal - o(n log(n))

update:

as jb nizet mentioned in comment, set (treeset) cannot contain duplicates. list (arraylist) can. if performance of import , there lot of elements , need store sorted elements allowing duplicates, can store in treeset, need implement counting (add() element.count++, , remove() element.count-- example).

java sorting date

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