http://www.infoq.com/presentations/Null-References-The-Billion-Dollar-Mistake-Tony-Hoare http://www.infoq.com/presentations/Null-References-The-Billi... I ofte

http://www.infoq.com/presentations/Null-References-The-Billion-Dollar-Mistake-Tony-Hoare http://www.infoq.com/presentations/Null-References-The-Billi... I often see code such as: public Object getObject() { return this.object; } I favour lazy initialization combined with self-encapsulation: private Object getObject() { Object o = this.object; if( o == null ) { o = createObject(); this.object = o; } return o; } This is thread-safe and allows injecting new behaviour via polymorphism (overriding the "create" methods in a subclass), which adheres to the Open-Closed Principle. It also eliminates the possibility of accidentally dereferencing nulls. It could even be implemented as a language feature: public class C { nullsafe String name; public void greeting() { System.out.printf( "Hello, %s\n", getName() ); } } Where the "nullsafe" keyword automatically generates a private accessor and corresponding protected creation method.