String filePath = new File("").getAbsolutePath() + "/src/file/" + "waitUse" + ".txt";
            FileInputStream inputStream = new FileInputStream(filePath);
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
            String lineString;
                   while ((lineString = bufferedReader.readLine()) != null) {
                
            }
            
bufferedReader.close();
            inputStream.close();

String filePath2 = "C:/Users/Administrator/Desktop/result.txt";
            File file = new File(filePath2);
            if(file.exists()){
                file.delete();
            }

            file.createNewFile();
            FileOutputStream fileOutputStream = new FileOutputStream(filePath2);
            OutputStreamWriter outputStreamWriter = new OutputStreamWriter(fileOutputStream);
            BufferedWriter bufferedWriter = new BufferedWriter(outputStreamWriter);
            
 bufferedWriter.write(content + "\n");
            bufferedWriter.close();// 必須加入，否則快取區未滿時不寫入，最後會有部分內容缺失
            fileOutputStream.close();