使用java实现多线程下载，包含断点续传。-use multi-threaded download, including HTTP.

文件多线程下载，支持断点续传，非常好的例子-mutiple file download，support stop-point download，good example

实现本地程序从远程服务器下载文件。保存到本地。同时，具备断点续传的功能。可以在下载一部分的情况下，再次下载从断点处继续下载。-Implement a local program to download files a remote server. Saved locally. At the same time, with the functions of HTTP. You can download a part in the case, once again download continu