public static void main(String[] args) { File f1 = new File("D:/JavaTest/1.txt"); File f2 = new File("D:/JavaTest/2.txt"); File f3 = new File("D:/JavaTest/3.txt"); String path = "D:/JavaTest/4.txt"; joinText(path, f1, f2, f3); } /** * 把所有的 file 内容合并到 path 对应的文件中 * @param path * @param files */ public static void joinText(String path, File ...files) { try { FileOutputStream fos = new FileOutputStream(path, true); for (File file : files) { FileInputStream fis = new FileInputStream(file); int length = 0; byte[] bytes = new byte[1024]; while ((length = fis.read(bytes)) != -1) { fos.write(bytes, 0, length); } fis.close(); // 回车换行 fos.write(" ".getBytes()); } fos.close(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } }