Java 隨機生成手機號：三段式號段+四位+四位更真實

實現思路

手機號 11 位：號段(3位) + 中間4位 + 尾號4位。三段式隨機性更強。

代碼示例

Random random = new Random();
String[] prefixes = {"130","131","132","133","134","135","136","137","138","139",
                     "150","151","152","153","155","156","157","158","159",
                     "180","181","182","183","184","185","186","187","188","189",
                     "170","171","173","175","176","177","178","179"};

String phone = prefixes[random.nextInt(prefixes.length)]
             + String.format("%04d", random.nextInt(10000))
             + String.format("%04d", random.nextInt(10000));
System.out.println(phone);

Random 需設置種子（如 System.currentTimeMillis()）以獲取不同序列。參考：Random 用法