Android Studio的笔记--随机数

String

获取 x 位 由0到9组成的随机字符串。
调用方法

Log.i("lxh", "获取由数字0到9组成的随机字符串：" + getStr(12));

函数

public String RandomStr(int length) {String characters = "0123456789";Random random = new Random();StringBuilder sb = new StringBuilder(length);for (int i = 0; i < length; i++) {int randomIndex = random.nextInt(characters.length());char randomChar = characters.charAt(randomIndex);sb.append(randomChar);}return sb.toString();}private static Set<String> stringSet = new HashSet<>();public boolean isRepeat(String str) {if (stringSet.size() >= 10000) {stringSet.clear();}if (!stringSet.contains(str)) {stringSet.add(str);return true;}return false;}public String getStr(int length) {String back = "";while (true) {String ss = RandomStr(length);Log.d("TAG", "rs=" + ss);if (isRepeat(ss)) {back = ss;break;}}return back;}

未完待续…

与君共勉！待续
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