Class FileBasedDiscovery

java.lang.Object
com.loomcache.server.discovery.FileBasedDiscovery
All Implemented Interfaces:
DiscoveryStrategy
public class FileBasedDiscovery extends Object implements DiscoveryStrategy
File-based discovery strategy that reads peers from a local file.

The file is watched for changes and automatically reloaded. File format: one peer per line, comma-separated nodeId,host,port. Example: node-1,192.168.1.10,5701 node-2,192.168.1.11,5701

Watches file using WatchService on a virtual thread. Thread-safe.

  • Constructor Details

    • FileBasedDiscovery

      public FileBasedDiscovery(Path peersFilePath)
      Create a file-based discovery strategy.
      Parameters:
      peersFilePath - path to peers file (e.g., "peers.txt")

  • Method Details

    • start

      public void start() throws Exception
      Description copied from interface: DiscoveryStrategy
      Start the discovery strategy.

      Initializes the discovery mechanism and starts any background threads or I/O operations (e.g., watching files, listening to multicast, resolving DNS). Implementations must handle errors gracefully and should not leave resources in an inconsistent state if startup fails.

      Specified by:
      start in interface DiscoveryStrategy
      Throws:
      Exception - if startup fails; specific exceptions depend on implementation

    • stop

      public void stop()
      Description copied from interface: DiscoveryStrategy
      Stop the discovery strategy and release resources.

      Cleanly shuts down the discovery mechanism, including stopping any background threads and closing I/O resources. Safe to call multiple times and must be idempotent (calling twice should have no additional effect).

      Specified by:
      stop in interface DiscoveryStrategy

    • discoverPeers

      public List<PeerAddress> discoverPeers()
      Description copied from interface: DiscoveryStrategy
      Discover available peers.

      Returns a snapshot of currently known peers. If no peers are available, an empty list is returned (not null). The returned list is mutable and modifications should not affect internal strategy state.

      Specified by:
      discoverPeers in interface DiscoveryStrategy
      Returns:
      list of discovered peer addresses; empty list if none available

    • getName

      public String getName()
      Description copied from interface: DiscoveryStrategy
      Get the name of this discovery strategy.

      Used for logging, metrics, and debugging purposes.

      Specified by:
      getName in interface DiscoveryStrategy
      Returns:
      human-readable strategy name (e.g., "FileBasedDiscovery", "MulticastDiscovery")

    • toString

      public String toString()
      Overrides:
      toString in class Object