enum in Java https://www.geeksforgeeks.org/enum-in-java/ Enumerations serve the purpose of representing a group of named constants in a programming language. For example, the 4 suits in a deck of playing cards may be 4 enumerators named Club, Diamond, Heart, and Spade, belonging to an ...
⭐️ [참고 - EnumSet과 EnumMap](https://www.geeksforgeeks.org/difference-between-enummap-and-enumset-in-java/) ## 6. 면접질문 1. class와 enum의 차이점은 무엇인가? 2. enum을 어떤 상황에서 사용했고, 사용한 이유가 무...
简化Java中Enum类的方法: 1. 使用Enum类来表示一组固定的常量值,可以使用关键字enum来定义,如: ``` public enum Color { RED, GREEN, B...
A recent post on the OpenJDKcompiler-dev mailing listtitled “about Enum.values() memory allocation” observes that “Enum.values()allocates a significant amount of memory when called in a tight loop as it clones the constant values array.” The poster of that message adds that this “is p...
原文地址:https://examples.javacodegeeks.com/java-basics/java-enumeration-example/ ===原文讲解也是比较细致,大略观之,以快图之。=== 1.Enum示例 Day.java public enum Day { SUNDAY(1), MONDAY(2), TUESDAY(3), WEDNESDAY(4), THURSDAY(5), FRIDAY...
class Geeks { static void isDivisibleByPrime (int n) { int a = 2; int b = 3; int c = 11; Scanner sc = new Scanner(System.in); int N = sc.nextInt(); if (N % 2 == 0){ System.out.println("Two"); }else if (N % 3 == 0){ System.out.println("Three"); }else ...
Exceptioninthread"main"java.lang.NullPointerException at java.util.EnumMap.typeCheck(EnumMap.java:743)at java.util.EnumMap.put(EnumMap.java:267)at java.util.EnumMap.put(EnumMap.java:79)at com.fsx.maintest.Main.main(Main.java:40)