Java实现ftp 断点 上传 [][实现立即给分]

    public boolean upload(String remote, String fileName, String local) throws IOException {        ftp.enterLocalPassiveMode();        if(fileName.endsWith(".rar") || fileName.endsWith(".zip") || fileName.endsWith(".jar")) {            ftp.setFileType(FTPClient.BINARY_FILE_TYPE); //2进制文件时,防止文件损坏        }        boolean result;                ftp.changeWorkingDirectory(remote); //进入ftp目录        boolean isExists = false;        FTPFile[] files = ftp.listFiles();        for (int i = 0; i < files.length; i++) {            FTPFile file = files[i];            if(fileName.equals(file.getName())) {                isExists = true;                break;            }        }//        String ftpdirpath = CCRUTIL.getEmisProp("FTPDIRPATH");        File fRemote = null;        fRemote = new File("\\\\Zhntm01\\Download\\"+remote.substring(1)+fileName);  [color=#FF0000]// (这里要new file吗? 用机器名的方式可以找到文件, 用"ftp://....的方式找不到文件")[/color]//        isExists = false;        if(isExists) {            //文件存在时, 使用断点上传方式            long fileSize = fRemote.length(); //未下载完成的文件大小            System.out.println("fileSize:" + fileSize);                        RandomAccessFile randomAccessFileRemote = new RandomAccessFile(fRemote, "rw");  //随机方位读取   [color=#FF0000]  (文件禁止访问读写 报错)[/color]            randomAccessFileRemote.seek(fileSize);  //定位指针到fileSize位置                        File fLocal = new File(local);            RandomAccessFile randomAccessFileLocal = new RandomAccessFile(fLocal, "r");            randomAccessFileLocal.seek(fileSize);                        int len = 0;            byte[] bt = new byte[1024];            while ((len = randomAccessFileLocal.read(bt)) > 0) {                randomAccessFileRemote.write(bt, 0, len);            }            randomAccessFileLocal.close();            randomAccessFileRemote.close();            result = true;        } else {            //不存在时, 直接上传            File f = new File(local);            FileInputStream in = new FileInputStream(f);            result = ftp.storeFile(remote + fileName, in);            in.close();        }        return result;    }