Over a million developers have joined DZone.
{{announcement.body}}
{{announcement.title}}

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

DZone's Guide to

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 ·
Free Resource

Get the Edge with a Professional Java IDE. 30-day free trial.

Image title


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.

Get the Java IDE that understands code & makes developing enjoyable. Level up your code with IntelliJ IDEA. Download the free trial.

Topics:
java ,removeif ,java performance ,collections

Opinions expressed by DZone contributors are their own.

{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}