java随即产生8位数的密码

//JAVA 随机产生一个8位数的密码
public static String getRandomPwd(){
Random rd = new Random();
String n = "";
int getNum;
int getNum1;
do {
getNum = Math.abs(rd.nextInt()) % 10 + 48;// 产生数字0-9的随机数
getNum1 = Math.abs(rd.nextInt())%26 + 97;//产生字母a-z的随机数
char num1 = (char) getNum;
char num2 = (char) getNum1;
String dn = Character.toString(num1);
String dn1 = Character.toString(num2);
if(Math.random()>0.5){
n += dn;
}else{
n += dn1;
}
} while (n.length() < 8 );

return n;
}