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Data, however, is managed by several classes since it is streamed, rather than read and then written (a good design for a proxy cache, but which complicates things for us). The relevant classes are

• handler.BaseHandler
• proxy.PartialCacher
• ...

Both interfaces (lucene and rabbit) want to deal with streams, so I have defined a set of classes that allow you to pass references to streams across process boundaries. RemoteIO, I define a detailed interface for remote streams. The code is in CVS under the package remoteio.

With remote streams, the interface to the RemoteRepository works as follows

• Somebody adds a cache entry, based on the HTTP header. I think this is BaseHandler
  • Adding an NCacheEntry to the NCache causes the cache to send an RMI call to the RemoteRepository which creates a pending entry, and returns a RemoteOutputStream
  • The RemoteOutputStream is added to the NCacheEntry
• Next, BaseHandler adds the stream from the cache to the MultiStream that it maintains to multiplex the data from the HTTP response to the client and a file. The RemoteOutputStream replaces that file.
• Finally, when the stream is closed, the RemoteRepository is notified, and the new cache data is indexed.