Class DiscoveryHealthChecker

java.lang.Object
com.loomcache.server.discovery.DiscoveryHealthChecker
public class DiscoveryHealthChecker extends Object
Health checker for validating discovered peer addresses.

Detects when a discovery strategy returns stale, unreachable, or incorrect addresses. Can be used to validate discovery results before using them for cluster communication.

Validation Strategy

  • DNS lookup: verify the address is resolvable
  • TCP connectivity check (optional): attempt to connect to the peer port
  • Duplicate detection: identify duplicate addresses in the peer list
  • Valid port range: verify ports are in the valid range [1, 65535]

Thread Safety

Thread-safe. All checks are non-blocking and use lightweight validations. TCP connectivity checks are performed synchronously but with timeout.

  • Constructor Details

    • DiscoveryHealthChecker

      public DiscoveryHealthChecker(String strategyName, @Nullable io.micrometer.core.instrument.MeterRegistry meterRegistry)
      Create a discovery health checker.
      Parameters:
      strategyName - name of the discovery strategy being validated (for metrics and logging)
      meterRegistry - optional MeterRegistry for metrics (can be null)

  • Method Details

    • validate

      public DiscoveryHealthChecker.DiscoveryValidationResult validate(List<PeerAddress> peers, boolean checkTcpConnectivity)
      Validate a list of discovered peers.

      Performs multiple checks:

      • Validates address format and port ranges
      • Detects duplicate addresses
      • Verifies addresses are resolvable (DNS check)
      • Optionally verifies TCP connectivity in parallel
      Parameters:
      peers - list of discovered peer addresses
      checkTcpConnectivity - if true, attempts TCP connection to each peer (may slow validation)
      Returns:
      validation result containing valid peers and detected issues

    • validateQuick

      public DiscoveryHealthChecker.DiscoveryValidationResult validateQuick(List<PeerAddress> peers)
      Quick validation without TCP connectivity checks.
      Parameters:
      peers - list of discovered peer addresses
      Returns:
      validation result