让英文和数字随机生成java_Java生成随机字母和数字

public String getCharacterAndNumber(int length)

{

String val = "";

Random random = new Random();

for(int i = 0; i < length; i++)

{

String charOrNum = random.nextInt(2) % 2 == 0 ? "char" : "num"; // 输出字母还是数字

if("char".equalsIgnoreCase(charOrNum)) // 字符串

{

int choice = random.nextInt(2) % 2 == 0 ? 65 : 97; //取得大写字母还是小写字母

val += (char) (choice + random.nextInt(26));

}

else if("num".equalsIgnoreCase(charOrNum)) // 数字

{

val += String.valueOf(random.nextInt(10));

}

}

return val;

}