Java download manager

I need to get several huge files (several performances) from Java via FTP / HTTP Is there a ready-made Library (Java / command line tools) for easy download? Some obvious requirements are:

>Multi connection download – it should be possible to open several connections to the server to speed up the download (e.g. FlashGet / getright /...) > resume the download

Editor - I really don't want to write such a library, but steal (or pay) for the existing test production library Rsynch is irrelevant because I need to download files from HTTP and FTP sites. It is not used for internal file transfer

Solution

The HTTP protocol does support starting partial downloads at offset, but there is limited support for validating the local version of a file to ensure that it is not attached to the end of garbage (or something like that) If your environment permits, I recommend using the – partial option for Rsync It is designed to support this function from the command line

If you cannot use Rsync, you may want to try using the common HTTP client and using the range HTTP header to download blocks of manageable size