Polymorphism - prose of Java programmers

In Java programming language as implemented in JDK 5.0 there appear rather advanced kinds of polymorphism, even if they are hidden under different names. The notion of polymorphism unifies many concepts present in typed programming languages, not necessary object-oriented. We briefly define some varieties of polymorphism and trace them in Java. Java shows that industrial programming languages are able to express more abstract patterns using rather involved theoretical means, hence the working programmer has to be better educated in order to understand them, recognize them in different programming languages under different names and superficial syntax, and make good use of them