What is Enum in Java
Enum in Java is a keyword, a feature which is used to represent fixed number of well known values in Java, For example Number of days in Week, Number of planets in Solar system etc. Enumeration (Enum) in Java was introduced in JDK 1.5 and it is one of my favorite features of J2SE 5 among Autoboxing and unboxing , Generics, varargs and static import. One of the common use of Enum which emerged in recent years is Using Enum to write Singleton in Java, which is by far easiest way to implement Singleton and handles several issues related to thread-safety and Serialization automatically. By the way, Java Enum as type is more suitable to represent well known fixed set of things and state, for example representing state of Order as NEW, PARTIAL FILL, FILL or CLOSED. Enumeration(Enum) was not originally available in Java though it was available in other language like C and C++ but eventually Java realized and introduced Enum on JDK 5 (Tiger) by keyword Enum. In this Java Enum tutorial we will see different Enum example in Java and learn using Enum in Java. Focus of this Java Enum tutorial will be on different features provided by Enum in Java and how to use them. If you have used Enumeration before in C or C++ than you will not be uncomfortable with Java Enum but in my opinion Enum in Java is more rich and versatile than in any other language. . By the way, if you like to learn new concepts using book than you can also see Java 5.0 Tiger : A Developers notebook, I had followed this book while learning Enum, when Java 1.5 was first launched. This book has excellent chapter not only on Enum but also on key features of Java 1.5 and worth reading.
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Enum in Java is a keyword, a feature which is used to represent fixed number of well known values in Java, For example Number of days in Week, Number of planets in Solar system etc. Enumeration (Enum) in Java was introduced in JDK 1.5 and it is one of my favorite features of J2SE 5 among Autoboxing and unboxing , Generics, varargs and static import. One of the common use of Enum which emerged in recent years is Using Enum to write Singleton in Java, which is by far easiest way to implement Singleton and handles several issues related to thread-safety and Serialization automatically. By the way, Java Enum as type is more suitable to represent well known fixed set of things and state, for example representing state of Order as NEW, PARTIAL FILL, FILL or CLOSED. Enumeration(Enum) was not originally available in Java though it was available in other language like C and C++ but eventually Java realized and introduced Enum on JDK 5 (Tiger) by keyword Enum. In this Java Enum tutorial we will see different Enum example in Java and learn using Enum in Java. Focus of this Java Enum tutorial will be on different features provided by Enum in Java and how to use them. If you have used Enumeration before in C or C++ than you will not be uncomfortable with Java Enum but in my opinion Enum in Java is more rich and versatile than in any other language. . By the way, if you like to learn new concepts using book than you can also see Java 5.0 Tiger : A Developers notebook, I had followed this book while learning Enum, when Java 1.5 was first launched. This book has excellent chapter not only on Enum but also on key features of Java 1.5 and worth reading.