Java: Out with the Old, In with the New

Question

Java is nearing version 7. It occurs to me that there must be plenty of textbooks and training manuals kicking around that teach methods based on older versions of Java, whe

Answer 1

Improved singleton patterns. Technically these are covered under the popular answer enums, but it's a significant subcategory.

public enum Singleton {
    INSTANCE;

    public void someMethod() {
        ...
    }
}

is cleaner and safer than

public class Singleton {
    public static final Singleton INSTANCE = new Singleton();

    private Singleton() {
        ...
    }

    public void someMethod() {
        ...
    }
}