Learn from teacher Wang Enumeration (iii): Enum class API

Learn from teacher Wang Enumeration (iii): Enumeration API
Teacher: Wang Shaohua QQ Group No.: 483773664

First, enumerate the class API

The enumeration classes declared in Java are children of the Java.lang.Enum class that inherit all the methods of the enum class. Common methods:

Name (): Returns the names of this enumeration constant

Ordinal (): Returns the ordinal of an enumerated constant (its position in the enumeration declaration, where the initial constant ordinal is zero

valueof (Class enumclass, String name): Returns an enumeration constant of the specified enumeration type with the specified name

valueof (String name): Returns the current enumeration type with the specified name

VALUES () This method, although not found in the JDK document, has the method for each enumeration class, which iterates through all the enumeration values of the enumeration class

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Second, enumeration class API instance

Public class enumtest {    public static void main (String[]  args)  {        //Returns the name of the enumeration type          system.out.println (Grade.a.name ());         // Returns the subscript         system.out.println (Grade.a.ordinal ()) of the enumeration type;         //to get an enumerated object through a string         String  Value= "D";         //. Gets the current enumeration          grade grade = grade.valueof (value);         System.out.println (Grade.name () +grade.getvalue () +grade.getlocstring ());         //second, through the parent class         grade grade2 = enum.valueof (Grade.class, value);  &Nbsp;      system.out.println (Grade2.name () +grade2.getvalue () + Grade2.getlocstring ());                  //get all the instance objects         Grade[] grades =  Grade.values ();        for  (grade g : grades)  {            system.out.println ( G.getlocstring () + "----");        }         //get the object by subscript         int index = 2;         grade[] grades2 = grade.values ();         Grade grade3 = grades2[index];         system.out.println (index+ "----" +grade3.name());     }} 

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Learn from teacher Wang Enumeration (iii): Enum class API