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Java Holiday Calendar 2016 (Day 4): Use RemoveIf in Java Collections

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Java Holiday Calendar 2016 (Day 4): Use RemoveIf in Java Collections

If you want to remove elements from a collection quick, fast, and in a hurry, take a look at removeIf(), which should save you ton of time over manual iterations.

· Java Zone
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Today's tip is to use the removeIf() method (that all collection classes like List have) rather than manually iterating over the elements and removing them. For large data sets, removeIf() can be orders of magnitudes faster than other methods. It also looks much better in your code. Why? Read more here and see for yourself! In the meantime, let's see how to put it to use.

Do This

items.removeIf(i -> predicate(i));


Don't Do This:

for (Iterator it = items.iterator(); it.hasNext();) {  
    if (predicate(it.next())) {
        it.remove();    
    }
}


Follow the Java Holiday Calendar 2016 with small tips and tricks all the way through the winter holiday season.

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Topics:
java ,removeif ,java performance ,collections

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