[Java] Are you using them without thinking? Correct usage and characteristics of List, Set, and Map

Are you just using ArrayList whenever you need to group data?What are the specific scenarios where Set or Map are the correct ...
Ars Technica

Java: ArrayList.contains(Object o) isn't calling the correct equals method

I have a class, say TextHolder, that overrides Object.equals() to return true if both strings in each object are equal - <tt>new TextHolder("Hello World!").equals(new ...