grizzly-sendfile is an extension for grizzly, the http connector of GlassFish application server. grizzly-sendfile is highly optimized for sending static files over HTTP and adds the "X-Sendfile" functionality to grizzly or GlassFish applications. This allows applications to offload file downloading functionality to the application server, which can take full advantage of lower level APIs like NIO to deliver files to clients very efficiently. See the wiki for more info.
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