@VisibleForTesting
  Deque<Connection> getDeque() {
    return connections;
  }
Passivate and add the given connection to this manager as its last, lowest priority connection.

@param connection the connection to passivate and add
@param accessed true if the connection was used by the caller, false otherwise
geode-core/src/main/java/org/apache/geode/cache/client/internal/pooling/AvailableConnectionManager.java