java.lang.Object
net.i2p.router.networkdb.kademlia.SegmentedNetworkDatabaseFacade
net.i2p.router.networkdb.kademlia.FloodfillNetworkDatabaseSegmentor
public class FloodfillNetworkDatabaseSegmentorextends SegmentedNetworkDatabaseFacade
Default implementation of the SegmentedNetworkDatabaseFacade.

This is a datastructure which manages (3+Clients) "sub-netDbs" on behalf of an I2P router, each representing it's own view of the network. Normally, these sub-netDb's are identified by the hash of the primary session belonging to the client who "owns" a particular sub-netDb.

There is one "Special" netDb which has a non-hash name. This is used for the operation of router itself and not clients, in particular when acting as a floodfill:

- Main NetDB: This is the netDb we use if or when we become a floodfill, and for direct interaction with other routers on the network, such as when we are communicating with a floodfill.

It is possible that it may be advantageous some day to have other netDb's for specific use cases, but that is not the purpose of this class at this time.

And there are an unlimited number of "Client" netDbs. These sub-netDbs are intended to contain only the information required to operate them, and as such most of them are very small, containing only a few LeaseSets belonging to clients. Each one corresponds to a Destination which can receive information from the netDb, and can be indexed either by it's hash or by it's base32 address. This index is known as the 'dbid' or database id.

Users of this class should strive to always access their sub-netDbs via the explicit DBID of the destination recipient, or using the DBID of the special netDb when it's appropriate to route the netDb entry to one of the special tables.

  • Field Details

    • _log

      private final Log _log
      Logger for this class.

    • _context

      private final RouterContext _context
      The router context the segments live in.

    • MAIN_DBID

      public static final Hash MAIN_DBID
      Database id of the special main netDb, deliberately null so it is never confused with a client's hash-keyed id.

    • _mainDbid

      private final FloodfillNetworkDatabaseFacade _mainDbid
      The facade holding the main database.

  • Constructor Details

    • FloodfillNetworkDatabaseSegmentor

      public FloodfillNetworkDatabaseSegmentor(RouterContext context)
      New segmentor with the given RouterContext, containing a default, main netDb and prepared to add client netDbs.
      Parameters:
      context - the router context supplying the log manager and the client netDb facades this segmentor creates and queries

  • Method Details

    • getSubNetDB

      private NetworkDatabaseFacade getSubNetDB(Hash id)
      Retrieves the FloodfillNetworkDatabaseFacade object for the specified ID. If the ID is null, the main database is returned.
      Parameters:
      id - the ID of the FloodfillNetworkDatabaseFacade object to retrieve
      Returns:
      the FloodfillNetworkDatabaseFacade object corresponding to the ID or null if it does not exist.

    • shutdown

      public void shutdown()
      If we are floodfill, turn it off and tell everybody for the _mainDbid.
      Specified by:
      shutdown in class SegmentedNetworkDatabaseFacade

    • startup

      public void startup()
      Start up the _mainDbid.
      Specified by:
      startup in class SegmentedNetworkDatabaseFacade

    • mainNetDB

      public NetworkDatabaseFacade mainNetDB()
      The main netDb, the one we will use if we are a floodfill.
      Specified by:
      mainNetDB in class SegmentedNetworkDatabaseFacade
      Returns:
      may be null

    • clientNetDB

      public NetworkDatabaseFacade clientNetDB(Hash id)
      The client netDb for the given id. Will return the "main" netDb if the dbid is null.
      Specified by:
      clientNetDB in class SegmentedNetworkDatabaseFacade
      Parameters:
      id - the destination hash naming which client sub-database to use
      Returns:
      non-null, the main netDb if the client netDb does not exist