java - 在枚举单例中调用参数化构造函数？

Question

我有这个枚举单例类:

enum C1 {
    INSTANCE("");

    C1(String s) {
        System.out.println("with param = " +s);
    }
    C1() {
        System.out.println("without param");
    }   
    public void g() {
        System.out.println("inside g");
    }
}

public class Main {
    public static void main(String s[]) {
        C1.INSTANCE.g();
        C1.INSTANCE.g();

    }
}

如何通过传递自定义参数使用 INSTANCE 调用 C1(String s) 构造函数？

Answer 1

你可以有这样的东西

    enum C1 {
        WITH_PARAM("value"),
        EMPTY();

        private String value;
        C1(String s) {
            System.out.println("with param = " +s);
            value=s;
        }
        C1() {
            System.out.println("without param");
        }
        public void g() {
            System.out.println("inside g, value is "+value);
        }
    }

        public static void main(String s[]) {
            C1.EMPTY.g();
            C1.WITH_PARAM.g();

        }