Using Java generics

Gosu can directly access types that use Java generics. In typical code, Gosu works identically to Java.

The runtime information about a type that uses generics is different for Java and Gosu generic types. You can access this information by using the typeof operator:

• The Java compiler erases the parameterization of the type during the compilation to Java byte code. At run time, the type ArrayList<Integer> for a Java type appears just as ArrayList. This Java behavior is known as type erasure.
• If the type is defined in Gosu, the runtime type retains the parameterization of the generic type. At run time, the type ArrayList<Integer> for a Gosu type appears as ArrayList<Integer>. This Gosu behavior is known as type reification.

See also

• Compatibility of Gosu generics with Java generics