Difference between Class and Class<?>

Question

What is the difference between a Class and a Class declaration.

• Class a;
• Class b;

Answer 1

Class javadoc:

Type Parameters: T - the type of the class modeled by this Class object. For example, the type of String.class is Class. Use Class if the class being modeled is unknown.

Use of Class without the type parameter is similar to using any generic class (Map, List, etc.) without the type parameter - either it's a pre-1.5 legacy usage or it's just a segment of code that does not care about unchecked type casting.