Java Enum and Its Superclass

All java enum E implicitly extends java.lang.Enum<E>. Since java doesn't allow multiple inheritance, enum types can't have superclass. They can't even extend from java.lang.Enum, nor java.lang.Object. It also means enum A can't inherit or extend enum B.

For example, the following is an invalid enum declaration:

public enum MyType extends Object {
ONE, TWO
}

Compiler error:

MyType.java:3: '{' expected
public enum MyType extends Object {
MyType.java:6: identifier expected
2 errors

The correct form should be:

public enum MyType {
ONE, TWO
}

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• Java enum examples
• Custom String Values for Enum
• Enum wrapper for javax.transaction.Status
• Enum wrapper for javax.transaction.Status (2)

Tags: enum, java