Arrays and Enumerated Types
Trail: The Reflection API

Lesson: Arrays and Enumerated Types

From the Java virtual machine's perspective, arrays and enumerated types (or enums) are just classes. Many of the methods in Class may be used on them. Reflection provides a few specific APIs for arrays and enums. This lesson uses a series of code samples to describe how to distinguish each of these objects from other classes and operate on them. Various errors are also be examined.


Arrays have a component type and a length (which is not part of the type). Arrays may be maniuplated either in their entirety or component by component. Reflection provides the java.lang.reflect.Array class for the latter purpose.

Enumerated Types

Enums are treated very much like ordinary classes in reflection code. Class.isEnum() tells whether a Class represents and enum. Class.getEnumConstants() retrieves the enum constants defined in an enum. java.lang.reflect.Field.isEnumConstant() indicates whether a field is an enumerated type.

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