有没有可能将数值赋给Java中的枚举？
在Java中有这样的可能吗？ 一个人可以分配自定义数值来枚举Java中的元素？
public enum EXIT_CODE { A=104, B=203; } public enum EXIT_CODE { A(104), B(203); private int numVal; EXIT_CODE(int numVal) { this.numVal = numVal; } public int getNumVal() { return numVal; } }
是的 ，然后是一些例子，从文档：
public enum Planet { MERCURY (3.303e+23, 2.4397e6), VENUS (4.869e+24, 6.0518e6), EARTH (5.976e+24, 6.37814e6), MARS (6.421e+23, 3.3972e6), JUPITER (1.9e+27, 7.1492e7), SATURN (5.688e+26, 6.0268e7), URANUS (8.686e+25, 2.5559e7), NEPTUNE (1.024e+26, 2.4746e7); // in kilograms private final double mass; // in meters private final double radius; Planet(double mass, double radius) { this.mass = mass; this.radius = radius; } private double mass() { return mass; } private double radius() { return radius; } // universal gravitational // constant (m3 kg-1 s-2) public static final double G = 6.67300E-11; double surfaceGravity() { return G * mass / (radius * radius); } double surfaceWeight(double otherMass) { return otherMass * surfaceGravity(); } public static void main(String[] args) { if (args.length != 1) { System.err.println("Usage: java Planet <earth_weight>"); System.exit(-1); } double earthWeight = Double.parseDouble(args[0]); double mass = earthWeight/EARTH.surfaceGravity(); for (Planet p : Planet.values()) System.out.printf("Your weight on %s is %f%n", p, p.surfaceWeight(mass)); } }
假设EXIT_CODE是指System . exit System . exit （exit_code），那么你可以做
enum ExitCode { NORMAL_SHUTDOWN ( 0 ) , EMERGENCY_SHUTDOWN ( 10 ) , OUT_OF_MEMORY ( 20 ) , WHATEVER ( 30 ) ; private int value ; ExitCode ( int value ) { this . value = value ; } public void exit ( ) { System . exit ( value ) ; } }
那么你可以把下面的代码放在适当的位置
ExitCode . NORMAL_SHUTDOWN . exit ( ) '
扩展Bhesh Gurung的分配值的答案，您可以添加明确的方法来设置值
public ExitCode setValue( int value){ // A(104), B(203); switch(value){ case 104: return ExitCode.A; case 203: return ExitCode.B; default: return ExitCode.Unknown //Keep an default or error enum handy } }
从调用应用程序
int i = 104; ExitCode serverExitCode = ExitCode.setValue(i);
//从现在开始你已经有效的枚举了
[无法评论他的答案，因此单独张贴]
