将无法被继承)而且该类继承自java.lang.Enum类,该类是一个抽象类(稍后我们会分析该类中的主要方法),除此之外,编译器还帮助我们生成了7个Day类型的实例对象分别对应枚举中定义的7个日期,这也充分说明了我们前面使用关键字enum定义的Day类型中的每种日期枚举常量也是实实在在的Day实例对象,只不过代表的内容不一样...
importorg.example.onjava.onjavaUtils.Enums; importjava.util.Iterator; /** *@AuthorCoder_Pans *@Date2022/11/20 09:32 *@PackageName:org.example.onjava.senior.example01enum.desgin *@ClassName: Mail *@Description: TODO 邮件建模 *@Version1.0 */ publicclassMail{ enumGeneralDelivery{YES,NO1,NO...
而枚举则不同,在序列化的时候Java仅仅是将枚举对象的name属性输出到结果中,反序列化的时候则是通过Enum的valueOf()方法来根据名字查找枚举对象。同时,编译器是不允许任何对这种序列化进行定制,因此禁用了writeObject、readObject、readObjectNoData、writeReplace和readResolve等方法。 代码语言:javascript 代码运行次数:0 运...
>[] enums = (Enum[]) enumClass.getEnumConstants(); for (Enum<?> anEnum : enums) { Map<String, Object> map = new HashMap<>(fieldList.size()); for (Field field : fieldList) { field.setAccessible(true); try { // 向map集合添加字段名称 和 字段值 map.put(field.getName(), ...
可以看到getOrCreate就是向constants Map中创建和获取新创建的constant对象。 使用ConstantPool ConstantPool是一个抽象类,如果我们需要新建一个枚举类池,可以直接继承ConstantPool,然后实现其中的newConstant方法。下面是一个使用的具体例子: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 public final class Foo ex...
Java introducedenumerationsin version 5. Enumerations provide a safe and clean way to manage constants. In this quick tutorial, we’ll explore how to compare aStringto anenumobject. 2. Introduction to the Problem First of all, let’s see anenumexample: ...
integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. Enum constants are only comparable to other enum constants of the same enum type. The natural order implemented by this method is the order in which the constants are declared...
$java EnumConstantsEnum name: Eon Enum constants: [HADEAN, ARCHAEAN, PROTEROZOIC, PHANEROZOIC] Eon.values(): [HADEAN, ARCHAEAN, PROTEROZOIC, PHANEROZOIC] Since enums are classes, other information may be obtained using the same Reflection APIs described in theFields,Methods, andConstructorssections...
// e.values(); // No values() in Enum for (Enum en : e.getClass().getEnumConstants()) System.out.println(en); } } 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 实现而非继承 所有的 enum 都继承自Java.lang.Enum类。由于 Java 不支持多重继承,所以你的 enum 不能再继承...
Returns the Class object corresponding to this enum constant's enum type. Two enum constants e1 and e2 are of the same enum type if and only if e1.getDeclaringClass() == e2.getDeclaringClass(). (The value returned by this method may differ from the one returned by theObject#getClassmethod...