Java code snippets _ 7

Package javaee. china. cxp;

Import org. junit. Test;

/**
* Function of enumeration: Some programs require a certain range of values instead of any data during runtime. JDK 5 used a custom class to solve this problem,
* After JDK 5, enumeration can be used directly.
* The New enum keyword in jdk5 is used to define an enumeration class.
* An enumeration can also contain constructors, fields, and methods.
*/
Public class Demo_7_emur {
 
@ Test
Public void test_6 (){
Print (Grade. );
Print2 (Grade2.A );
}
 
Public void print (Grade G ){
 
}
 
Public void print2 (Grade2G ){
 
}
 
/**
* The following method is replaced by the emur enumeration.
*/
Enum Grade2 {
 
A, B, C, D, E;
 
}
 
 
}

/**
* Jdk5 used custom classes to solve the problem.
* Privatize the Grade Constructor
* Provides a common static constructor.
*/
Class Grade {
 
Private Grade (){}
 
Public static final Grade A = new Grade ();
 
Public static final Grade B = new Grade ();
 
Public static final Grade C = new Grade ();
 
Public static final Grade D = new Grade ();
 
Public static final Grade E = new Grade ();
 
}