Java Enum internally inherits the Enum class, so it cannot inherit any other class, but it can implement many interfaces. We can have fields, constructors, methods, and main methods in Java enum.

從 Java Bytecode 可以發現，其實 `enum` 底層本身是個 `final class`, 也因此 `enum` 不能再繼承其他的 class (Java 是單一繼承)。 Constructor 設計成 __private__，所以工程師不能隨意自行產生值，只能使用內定的值或 `null`。 ## Scala 版本 ``` object DirectionScala extends ...

Introductionan enum type in java is a special data type that is defined whenever you need to define a variable with a set of predefined values such as days of the week, months of the year, items in a ...

Erfahren Sie, wie Sie Enumerationen in Java serialisieren und deserialisieren, die Vor- und Nachteile verschiedener Ansätze und die Best Practices, um es richtig zu machen.

Java developers have a choice for iterating collection of objects. Here's why the Java Iterator vs. Enumeration debate is all about the Iterator.

Although it is part of the java.util.concurrent package, the TimeUnit enum is useful in many contexts outside of concurrency .

The so-called typesafe enum construct has gained popularity since its increased coverage in several publications and admittance into the Sun JDK implementation. But be warned: this tip shows that ...

JPA and Hibernate enum mapping The Java enum, introduced in Java 5, will map to the underlying database without any intervention. The JPA framework, be it Hibernate or Toplink or DataNucleus, will ...

Enumeration is used to retrieve or traverse all the elements of particular collection of objects. Its not considered for collections but we can use it for legacy like Vectors. To use it we need to ...