JAVA隨機生成漢字

//自動生成名字（中文）
    public static String getRandomJianHan(int len) {
        String ret = "";
        for (int i = 0; i < len; i++) {
            String str = null;
            int hightPos, lowPos; // 定義高低位
            Random random = new Random();
            hightPos = (176 + Math.abs(random.nextInt(39))); // 獲取高位值
            lowPos = (161 + Math.abs(random.nextInt(93))); // 獲取低位值
            byte[] b = new byte[2];
            b[0] = (new Integer(hightPos).byteValue());
            b[1] = (new Integer(lowPos).byteValue());
            try {
                str = new String(b, "GBK"); // 轉成中文
            } catch (UnsupportedEncodingException ex) {
                ex.printStackTrace();
            }
            ret += str;
        }
        return ret;
    }
    
    //生成隨機用戶名，數字和字母組成,  
    public String getStringRandom(int length) {  
          
        String val = "";  
        Random random = new Random();  
          
        //參數length，表示生成幾位隨機數  
        for(int i = 0; i < length; i++) {  
              
            String charOrNum = random.nextInt(2) % 2 == 0 ? "char" : "num";  
            //輸出字母還是數字  
            if( "char".equalsIgnoreCase(charOrNum) ) {  
                //輸出是大寫字母還是小寫字母  
                int temp = random.nextInt(2) % 2 == 0 ? 65 : 97;  
                val += (char)(random.nextInt(26) + temp);  
            } else if( "num".equalsIgnoreCase(charOrNum) ) {  
                val += String.valueOf(random.nextInt(10));  
            }  
        }  
        return val;  
    }