Enum是enumeration(列举)的简写形式,包含在java.lang包中.熟悉C, C++, C#, 或 Pascal的人应该对列举有所了解,先看个例子:接口方法实现列举 一个enum是定义一组值的对象,它可以包括零个或多个值成员.它是属于enum类型的,一个enum对象中不可有两个或多个相同的属性或值.在此之前的java程序员一般是 用接口的方法实现列
Enums are used when we know all possible values at compile time, such as choices on a menu, rounding modes, command-line flags, etc. It is not necessary that the set of constants in an enum type stayfixedfor all time. A Java enumeration is a class type. Although we don’t need nee...
1. Enum Class 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 publicenumContainerPropertyConstants { RETAILER("retailer"), LINED("isLined"), BAGGING("bagging"), MISSING("missing"), MOVABLE("movable"), RESERVABLE...
Returns the name of this enum constant, as contained in the declaration. static <T extendsEnum<T>> TvalueOf(Class<T> enumType,Stringname) Returns the enum constant of the specified enum type with the specified name. Methods inherited from class java.lang.Object ...
java.util.EnumMap is a specialized java.util.Map implementation whose key is of Enum type. 2. All keys in EnumMap must be of a single Enum type while creating it. 3. The elements in EnumMap are maintained in the natural order of keys. 4...
Before going into the details, let's first understand the basic syntax of EnumMap and EnumSet in Java ? EnumMap syntax EnumMap<EnumClass, ValueType> map = new EnumMap<>(EnumClass.class); EnumSet syntax EnumSet<EnumClass> set = EnumSet.<EnumClass>of(EnumValue1, EnumValue2, ...); ...
Core Java Enums reference 1. Overview In this tutorial, we’ll learn what Java enums are, what problems they solve, and how some of their design patterns can be used in practice. Further reading: Java 5 first introduced theenumkeyword.It denotes a special type of class that always extends...
The enum data type in Java is supported when Java types map to PL/I structures. You can specify that it maps to the PL/I char type or the ordinal type.
Unlike other languages like C# or Java,Javascript Does Not Have Native Support for enums. There are several ways to implement enums in Javascript, and we’ll look at each of them in this post. However, in the absence of native language support, each implementation will have its own tradeof...
In Java, you can assign values to enums by defining a constructor and a private variable in the enum. For example an enum for Seasons of the year will have 4 constants:public enum Season {WINTER, SPRING, SUMMER, FALL}. This allows you to associate specific values with each enum constant...