disposeGroup static method

void disposeGroup(String groupId)

Removes every entry whose current groupId equals groupId. Subsequent lookup calls for those tokens return null.

Entries that were registered under groupId but later refreshed (cache hit) by a newer snapshot now carry the newer snapshot's groupId — those are NOT removed by this call. This is what lets older snapshot ids be disposed without invalidating refs the agent is still using.

No-op when no entry currently carries groupId.

Implementation

static void disposeGroup(String groupId) {
  // 1. Collect tokens to remove. Iterate before mutation to avoid
  //    concurrent-modification on the entries map.
  final List<String> toRemove = <String>[];
  final List<int> nodeIdsToRemove = <int>[];
  for (final MapEntry<String, RefEntry> entry in _entries.entries) {
    if (entry.value.groupId == groupId) {
      toRemove.add(entry.key);
    }
  }
  // 2. Drop entries.
  for (final String token in toRemove) {
    _entries.remove(token);
  }
  // 3. Drop dedupe-cache mappings whose token is gone. Iterate the
  //    node-id map separately because entries[X] just disappeared.
  for (final MapEntry<int, String> entry in _byNodeId.entries) {
    if (toRemove.contains(entry.value)) {
      nodeIdsToRemove.add(entry.key);
    }
  }
  for (final int nodeId in nodeIdsToRemove) {
    _byNodeId.remove(nodeId);
  }
}