在看Thinking in Java，有一段實(shí)在沒看懂package com.company.allAreTheObjective.Symbol;import java.util.*;/** * Created by Francis on 12/05/2016. */public class VowelsAndConsonants {    public static void main(String args[]){        Random rand = new Random(47);        for (int i = 0; i < 100; i++){            int c = rand.nextInt(26) + 'a';            System.out.print((char)c+","+ c +":");            switch(c){                case 'u' : System.out.println("vowel");break;                case 'w' : System.out.println("Sometimes a vowel");break;                default  : System.out.println("constant");            }        }    }}這一段為什么輸出恒為y,121:constantn,110:constantz,122:constantb,98:constantr,114:constantn,110:constanty,121:constant