[java] use the terms "type parameter" and "type argument"

Generic Types (The Java™ Tutorials > Learning the Java Language > Generics (Updated))
http://docs.oracle.com/javase/tutorial/java/generics/types.html


Type Parameter and Type Argument Terminology: Many developers use the terms "type parameter" and "type argument" interchangeably, but these terms are not the same. When coding, one provides type arguments in order to create a parameterized type. Therefore, the T in Foo is a type parameter and the String in Foo f is a type argument. This lesson observes this definition when using these terms.