What is difference between enum and final in Java?
There is a big difference: first, enum , is not a variable, it is a type. A final variable, say, an int , can have a single, preset value from among many possible values of int , while an enum variable (which could also be final ) can have a value from a set that you declare when defining the enum .
When should enum be used in Java?
Enums are lists of constants. When you need a predefined list of values which do represent some kind of numeric or textual data, you should use an enum. You should always use enums when a variable (especially a method parameter) can only take one out of a small set of possible values.
Do you think Java enums are more powerful than integer constants?
Yes. Java Enums provide many features that integer constants cannot. Enums can be considered as final classes with a fixed number of instances. Enums can implement interfaces but cannot extend another class.
What is the difference between enum and constant?
With a set of constants, any value of the same intrinsic type could be used, introducing errors. With an enum only the applicable values can be used.
How are enums better than constants?
Are enums static and final?
Enum contastants are static and final by default and cannot be changed after once it is created. Also Enums can be used in Switch statements like int and char data types.
Can enum values be changed?
Enum constants are implicitly static and final and you can not change their value once created. Enum in Java provides type-safety and can be used inside switch statements like int variables.
Can we use constants in enum?
A Java enum is a data type that stores a list of constants. You can create an enum object using the enum keyword. Enum constants appear as a comma-separated list within a pair of curly brackets.
Why do we use enums instead of constant strings in Java?
Enums limit you to the required set of inputs whereas even if you use constant strings you still can use other String not part of your logic. This helps you to not make a mistake, to enter something out of the domain, while entering data and also improves the program readability. Additionally you can always use your enums as a String if you desire.
What is the difference between enums and static fields?
Enums are type-safe, static fields are not. There is a finite number of values (it is not possible to pass non-existing enum value. If you have static class fields, you can make that mistake) Each enum can have multiple properties (fields/getters) assigned – encapsulation.
Why do enums have short and long names?
In the enum class itself, you use the short names. Because enums have methods, many low-level codes that would make heavy use of the constants could migrate from a business code to the enum class itself (either dynamic or static method). As we saw, migrating code to the enum reduces the long names uses even further.
Why do we need enums?
Technically one could indeed view enums as a class with a bunch of typed constants, and this is in fact how enum constants are implemented internally. Using an enum however gives you useful methods ( Enum javadoc) that you would otherwise have to implement yourself, such as Enum.valueOf.