java enum class example

This article mainly introduces the conversion of Enum and string in C # related data, the need for friends can refer to the following C # JSON conversion operations Enum type Enum provides a base class for enumerations, which can be of the base type except Any integral type outside of Char, using Int32 if the underlyi

An introduction to the type of Enum The enumeration type (enumerated type) appears early in the programming language and is used to include a similar set of values into one type. The name of this enumeration type is defined as a unique type descriptor, which is similar to the definition of a constant. However, compared to a constant type, an enumeration type can provide a larger range of values for the declared variable. For

. enummap; Package COM. aicent. test; The following content may be boring, but it is definitely worth a glimpse.1. Code:Public class State {Public static final int on = 1;Public static final int off = 0;} What's wrong? It's been a long time for everyone to do this. It's okay.First, it is not type-safe. You must make sure it is an intSecond, make sure that the range is 0 and 1.Finally, most of the time you print out, you only see 1 and 0, But the per

1. About Java Enum: People who have studied languages such as C + + should inkling the Enum type. An Enum is typically used to represent a set of constants of the same type. such as sex, date, month, color and so on. The benefits of constants for these properties are obvious, not only for a single

using the ToString () method.valueOf () is a static method defined in the enum that returns the corresponding enum instance based on the given name, and throws an exception if no instance of the given name exists.Java enumeration (enum) 7 common usesJDK1.5 introduces a new type--enumeration. In Java, although it is a

An enum is a shorthand form of a enumeration (enumeration) that is contained in a Java.lang package. Familiar with c,c++,c#, or Pascal should have an understanding of the list, first look at an example: Public enum Season {winter, Spring, Summer, fall} An enum is an object that defines a set of values, and it can inc

This article is taken from the csdn forum post Q: Question The tostring () method of the enum class can be different from several parameters, such:Enum. tostring ("D ");Enum. tostring ("N ");Enum. tostring ("G ");Enum. tostring ("F ");What do the parameters "N", "g", and

JDK1.5 introduces a new type--enumeration. In Java it is a "small" function, but to my development has brought "big" convenience. Usage One: Constants Before JDK1.5, we defined constants as: public static fianl ... Now that you have enumerations, you can group related constants into an enumeration type, and enumerations provide more methods than constants. public enum Color { RED, GREEN, BLANK

Package main; Public class EnumTest { /*** Normal Enumeration*/Public enum ColorEnum {Red, green, yellow, blue;}/*** You can add attributes and methods like ordinary classes for enumeration. You can add static and non-static attributes or methods for it.*/Public enum SeasonEnum {// Note: enumeration is written at the beginning; otherwise, an error occurs during c

Learn Java friends should know that Java from the beginning of the platform to play a non-independent banner, said "write once, run everywhere", actually speaking of irrelevant, the Java platform has another irrelevant that is language-independent, to achieve the language of independence, Then the Java System

An enum class has been added to the JDK1.5 that can be used to map to database tables. And it's very convenient to implement. Here's an example: Development environment: JDK 1.6 U2 Eclipse 3.3 There is a table in the database: Useruser It has two fields: 1, id;2, username, We map out an enum: public

It is not recommended to use Singleton1 and Singleton2,singleton3 basic to meet the requirements, SINGLETON5 support delay loading, but the implementation of a bit of trouble, effective Java authors recommend the enumeration to implement a single case, automatic support serialization mechanism , preventing deserialization from recreating new objects, and absolutely preventing multiple instantiations implementing a single

sqlTypeEnum = SqlTypeEnum.valueOf(token.toUpperCase()); If not, Java throws an exception:IllegalargumentexceptionNo Enum const class sqltypeenum. xxx I doReason for capital ProcessingThe reason is that the enumeration is in upper case (of course, if your enumeration is in lower case, you will be in lower case, but it is troublesome to mix and write). In fact,

Learn from teacher Wang Enumeration (iii): Enumeration APITeacher: Wang Shaohua QQ Group No.: 483773664First, enumerate the class APIThe enumeration classes declared in Java are children of the Java.lang.Enum class that inherit all the methods of the enum class. Common metho

background:today started a new project, because to get some code from the previous old project, so I looked at the company before the project code, found that there are defined constant class, there are enumeration classes, and then just think about the function of the two, then what is the difference between them, so decided to understand the next enum enumeration First, Introductionenum types in

an enum. Java code publicenumcolor{ red ("Red", 1), green ("green", 2), blank ("white", 3), yello ("Yellow", 4); // member variables privateStringname; privateintindex; // Construction Method privatecolor (stringname,intindex) { this.name=name; this.index=index; } // General method publicstaticstringgetname (int index) { for (colorc: color.values ()) NBsp { if (C.getindex () ==index) { returnc.

Enumeration (enum) and static members of a class (static)Enumeration represents a type that can be countedGender.javaenum Gender {male,Female,}Person.javapublic class Person {String name;int age;Gender gender;static String nation;/** * display()显示方法 * */void display() {System.out.println(String.format("姓名=%s，年龄=%d，性别=%s，国籍=%s", name, age,gender, Person.nation));}

Java enumeration class usage example This example describes the usage of Java enumeration classes. Share it with you for your reference. The details are as follows: ? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

Saw something, found that the Java enumeration is not very understanding, and then look for a check to remember.Why use enumerations? The enumeration was not jdk1.5 until after 1.5, and Java was not supported for enumeration. Why use enumerations?If a variable has only a few possible values, we can use an int, string, or other type of variable to represent it, although we can do this, but we can't guarantee

Java enum enumeration usage, javaenum Enumeration 1. Background: Before JDK1.5, we define constants as follows: public static final String RED = "RED "; When the enumeration type is added to JDK, We can group related constants into one enumeration class: public enum Color {RED, GREEN, BLUE;} This can be used as follow