public long getFileSize(final File file){if(file.isFile()){return file.length();}else{long total = 0;File files[] = file.listFiles();if(files == null)return 0;for(File f: files){total += getFileSize(f);}return total;}}

private long getFileSizebf(final ExecutorService service,final File file) throws InterruptedException, ExecutionException, TimeoutException{if(file.isFile())return file.length();else{final File files[] = file.listFiles();if(files == null)return 0;else{long total = 0;final List<Future<Long>> tasks = new ArrayList<Future<Long>>();for(final File f : files){tasks.add(service.submit(new Callable<Long>() {@Overridepublic Long call() throws Exception {// TODO Auto-generated method stub　　　　　　　　　　　　　　　　//进行递归,把子目录的文件大小返回return getFileSizebf(service, f);}}));}for(final Future<Long> fl : tasks){total += fl.get();}return total;}}}

public class FileOPBX1 implements FileOpI {@Overridepublic long getTotalSizeOfFilesInDir(File f) {long total = 0;final ExecutorService eService = Executors.newFixedThreadPool(100);// TODO Auto-generated method stubfinal List<File> dirs = new ArrayList<>();dirs.add(f);//初始化当前文件夹while (!dirs.isEmpty()) {//每次计算dir里面一集目录下的文件大小以及子目录final List<Future<SubDirAndSize>> part = new ArrayList<>();for (final File dir : dirs) {part.add(eService.submit(new Callable<SubDirAndSize>() {@Overridepublic SubDirAndSize call() throws Exception {// TODO Auto-generated method stubreturn getEveryDir(dir);}}));}dirs.clear();//目录分配任务完毕，清除//从返回的结果计算文件大小，并且把新的子目录添加到待计算文件夹for (final Future<SubDirAndSize> subdir : part) {try {final SubDirAndSize sas = subdir.get();total += sas.size;dirs.addAll(sas.subDirs);} catch (InterruptedException | ExecutionException e) {// TODO Auto-generated catch block
                    e.printStackTrace();}}System.out.println(dirs);}return total;}//计算当前一级目录下文件的大小以及子目录private SubDirAndSize getEveryDir(final File f) {long total = 0;final List<File> subDirs = new LinkedList<File>();if (f.isDirectory()) {final File[] sub = f.listFiles();if (sub != null) {for (final File dir : sub) {if (dir.isFile())total += dir.length();else {subDirs.add(dir);}}}}return new SubDirAndSize(total, subDirs);}public class SubDirAndSize {final public long size;final public List<File> subDirs;public SubDirAndSize(final long totalsize, final List<File> thesubDir) {size = totalsize;subDirs = Collections.unmodifiableList(thesubDir);}}}