生成大小字母以及数字混乱的6位验证码

需求：生成大小字母以及数字混乱的6位验证码

public class VerifyCode {
    public static String getCode(int length){
        String code = "";
        for(int i=0;i<length;i++){
            boolean boo = (int)(Math.random()*2)==0;
            if(boo){
                code += String.valueOf((int)(Math.random()*10));
            }else {
                int temp = (int)(Math.random()*2)==0?65:97;
                char ch = (char)(Math.random()*26+temp);
                code += String.valueOf(ch);
            }
        }
        return code;
    }

    public static void main(String[] args) {

        System.out.println(VerifyCode.getCode(6));
        System.out.println("-----------------");
        System.out.println(VerifyCode.getVerify(6));
    }

    public static String getVerify(int length){
        String code = "";
        String str = "0123456789qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASFGHJKLZXCVBNM";
        String[] strs = str.split("");
        for(int i = 0;i<length;i++){
            code += strs[(int)(Math.random()*strs.length)];
        }
        return code;
    }
}

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Random;

/**
 * @author Administrator
 *    随机生成6位验证码
 */
public class Test01 {
    public static void main(String[] args) {
        //创建一个ArrayList集合，存放生成的代码
        List<Object> list = new ArrayList();
        //for循环生成6位验证码
        for(int i = 0;i<6;i++) {
            //if语句交替判断生成数字或者字母
            if(i%2==0) {
                int b = (int)(Math.random()*10);//生成0~9的数字
                list.add(b);
            }else {
                boolean flag = false;
                do {
                    int a = (int)(Math.random()*58+65);//生成大小写字母的ASCII码
                    //if排斥多余的中间其他字符
                    if(!(a>=91&&a<=95)) {
                        String s = (char)a+"";//数字转字母
                        list.add(s);
                        flag = true;
                    }
                }while(!flag);
            }
        }
         Collections.shuffle(list);//shuffle随机排序
         String out = new String();
         for(Object s : list) {
             out+=s;
         }
         System.out.println(out.toString());
    }
}