Introduction to Java: modifiers cheatsheet

Modifiers in Java still seem tricky to me, so I'll try to put it as short as possible.

Modifiers are words that alter the class / method / variable behavior. The two main types are access and non-access modifiers.

1. Access modifiers alter visibility:

   • no modifier - the class is visible to its package
   • private - only to the class
   • public - to every class everywhere
   • protected - to the package and its subclasses

2. Non-access modifiers alter other functionalities:

   • static - makes the declaration class specific, not instance specific. It allows to use the method without an actual instance
   • final - doesn't allow the reference to change
   • abstract - for a method, declares that the method should be overriden in subclasses, for a class, that it cannot be instantiated, only subclassed