What does enum mean in java?

An enumeration is a data type used to represent fixed, unambiguous, and named values, ensuring that variables are limited to these predefined values. Its benefits include enhanced readability, maintainability, and reliability, eliminating hard-coded values, providing comparison and lookup operations, and ensuring data integrity. In Java, enumerations are created using the enum keyword. Enumeration constants can be used as variable types and provide convenient methods to compare and access enumeration values. Enumeration values ​​can also be easily processed using switch-case statements. Enumerations are widely used in scenarios such as representing state, defining options, and ensuring data consistency.

Enumerations in Java

What are enumerations?

An enumeration is a data type used to represent a fixed, unambiguous, and named set of values. It ensures that variables are limited to these predefined values.

Advantages of enumeration

• Enhance the readability, maintainability and reliability of the code.
• Eliminate hard-coded strings or numbers, improving scalability and flexibility.
• Convenient for comparison and search operations on enumeration values.
• Ensure data integrity and prevent illegal enumeration values.

Create an enumeration

Create an enumeration using the enum keyword, followed by the enumeration name and a list of enumeration constants:

public enum Weekday {
    MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY
}

Using Enumerations

Enumeration constants can be used as variable types:

Weekday today = Weekday.FRIDAY;

Enumerations also provide convenient methods to compare and access enumerations Values:

if (today == Weekday.FRIDAY) {
    // ...
}

Weekday nextDay = today.next();

Using the switch-case statement

Enumeration values ​​can be easily processed using the switch-case statement :

switch (today) {
    case MONDAY:
        // ...
    case TUESDAY:
        // ...
    // ...
}

Application of enumeration

Enumeration is widely used in various scenarios, including:

• Represents status (for example: status , permission level)
• Define a set of options (for example: menu options, language selection)
• Ensure data consistency (for example: database field type, business rules)

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