The other advantage of using Apache commons-collections CollectionUtils.isEmpty (or CollectionUtils.isNotEmpty) is that your if condition has less branches, so it is easier to reach a …

Sep 19, 2011 · 4 Pass java.text.Collator.getInstance() to Collections.sort method ; it will sort Alphabetically while ignoring case sensitive.

Eclipse Collections If you're using pairs that contain primitives, Eclipse Collections provides some very efficient primitive pair classes that will avoid all the inefficient auto-boxing and auto …

Every example I find is about doing this alphabetically, while I need my elements sorted by date. My ArrayList contains objects on which one of the datamembers is a DateTime object. On …

Again, to use Collections.sort, you need one of these to be true: The type must be Comparable (use the 1-arg sort) A Comparator for the type must be provided (use the 2-args sort) When to …

Unmodifiable collections are usually read-only views (wrappers) of other collections. You can't add to, remove from or clear them, but the underlying collection can change. Immutable …

Oct 10, 2008 · Avoid Apache Commons Collections. It’s not typesafe, there are no generics. Great if you use Java 1.4, but for Java 5 and above, I’d prefer Google Guava.

Usually an instance of java.util.Collection (although java.util.Map is officially also a part of the collections framework) Although the Collection interface can be implemented directly, usually …

java collections - keyset () vs entrySet () in map Asked 13 years, 10 months ago Modified 6 years, 10 months ago Viewed 122k times

Today I was happily coding away when I got to a piece of code I already used hundreds of times: Iterating through a Collection (here ArrayList) For some reason, I actually looked at the …