教えてエライ人2

gistfile1.java

interface Debugprintable {
    enum ErrStatus {
        NO_ERROR(0), FILE_ERROR(1), MEMORY_ERROR(2);
        private final int statusCode;
        private ErrStatus(int statusCode) {
            this.statusCode = statusCode;
        }
        @Override
        public String toString() {
            return Integer.toString(statusCode);
        }
    }
    String PREFIX = "ERROR:";
    void debugprint();
}


class Mynumber implements Debugprintable{
    private int a;
    private ErrStatus y;
    
    public Mynumber(int a) {
        this.a = a;
        setCode(a);
    }
    
    private void setCode(int x){
        switch (x) {
        case 100:
            y = ErrStatus.NO_ERROR;
            break;
        case 200:
            y = ErrStatus.FILE_ERROR;
            break;
        default:
            y = ErrStatus.MEMORY_ERROR;
        }
    }
    
    @Override
    public void debugprint() {
        System.out.println(PREFIX + y);
    }
    
}


//Debugprintable interface をメソッドの引数として使用する。
public class Mynumber2 {
    public void printDebug(Debugprintable debugprintable) {
        debugprintable.debugprint();
    }
    
    public static void main(String[] args) {
        Mynumber a = new Mynumber(100);
        Mynumber b = new Mynumber(200);
        Mynumber c = new Mynumber(500);
        
        Mynumber2 x = new Mynumber2();
        x.printDebug(a);
        x.printDebug(b);
        x.printDebug(c);
    }
}