def String genKey() { String key = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"; ArrayList<String> keyList = new ArrayList<>(); for (int i = 0; i < key.length(); i++) { keyList.add(String.valueOf(key.charAt(i))); } Collections.shuffle(keyList);//打乱 StringBuilder result = new StringBuilder(); for (String i : keyList) { result.append(i); } return result.toString(); } //加密字符串 def String encode(String text,String key){ StringBuilder stringBuilder = new StringBuilder(); for (int i=0;i<text.length();i++){ String c = new String(text.charAt(i)) int index = key.indexOf(c); if (index!=-1){ index++; if (index>=key.length()){ index = 0; } stringBuilder.append(key.charAt(index)); }else{ stringBuilder.append(c); } } return stringBuilder.toString(); }