Integer it = new Integer(i); //基本类型转换成封装类型 Integer it2 = i; //自动转换就叫装箱 自动拆箱类类型 -->基本类型 可以直接将类类型的元素赋给“=”一个基本类型的变量。不需要调用Integer的intValue方法 int i = 5; Integer it = new Integer(i); int i2 = it.intValue(); //封装类型...
Need to convert an integer to an enum in Java? The bad news is that it is not as easy as it should be, but the good news is that it is still easy! Consider the enum below. public enum PageType { ABOUT(1), CODING(2), DATABASES(3); private int value; private static Map map ...
THURSDAY,FRIDAY,SATURDAY,SUNDAY}publicclassEnumToIntExample{publicstaticvoidmain(String[]args){List<String>weekdays=newArrayList<>();weekdays.add("MONDAY");weekdays.add("TUESDAY");weekdays.add("WEDNESDAY");List<Integer>intValues=newArrayList<>();for(Stringweekday:weekdays){WeekdayenumValue=Weekday.v...
for(SexEnum sex: SexEnum.values()){ out.println("Enum member variable: "+sex); } //use another way to show out.println("---use another way to show--- "); for(int i =0;i<SexEnum.values().length;i++){ out.println("Enum member variable: "+SexEnum.values()[i]); } //com...
方法一:使用Enum类的values()方法和循环: java public static MyEnum intToEnum(int value) { for (MyEnum myEnum : MyEnum.values()) { if (myEnum.getValue() == value) { return myEnum; } } throw new IllegalArgumentException("Invalid integer value: " + value); } 方法二:使用自定义的转...
compareTo() ,valueOf()方法 调用valueOf() 方法获取枚举的一个成员,再调用 compareTo() 方法进行比较,并输出结果 Enum默认实现了java.lang.Comparable接口。 枚举类型 变量=枚举类型.valueOf("枚举值") enumSex { MALE,FEMALE; } publicclassTestEnum {publicstaticvoidcompare(Sex s) {for(inti = 0; i ...
而不是在每个enum中重复代码。这是可能的,因为enum可以实现接口,因此您可以定义访问int值的统一方式:
>&Enumerator>Map<Integer,String>enumToOptions(Class<E>enumClazz){// 合并时检查 key 是否重复BinaryOperator<String>merge=(u,v)->{thrownewIllegalStateException(String.format("Duplicate key %s",u));};Enumerator[]enumConstants=enumClazz.getEnumConstants();returnStream.of(enumConstants).collect(...
To illustrate, let’s add the atomic number as anintand the atomic weight as afloat: publicenumElement{ H("Hydrogen",1,1.008f), HE("Helium",2,4.0026f),// ...NE("Neon",10,20.180f);privatestaticfinalMap<String, Element> BY_LABEL =newHashMap<>();privatestaticfinalMap<Integer, Element...
在Java编程中,枚举(Enum)是一个非常有用的特性,通常用于表示固定集合的常量。而在某些情况下,我们需要将一个整数(int)转换为枚举类型,或者从枚举类型获取到一个整数值。本文将详细介绍如何实现Java中int与枚举值之间的转换。 整体流程 下面是实现整件事情的流程概述: ...