@Override
  public String toString() {
    if (identity != null
        && ((InternalDistributedMember) getDistributedMember()).getMembershipPort() == 0) {
      return toStringNoCache();
    }
    if (_toString == null) {
      _toString = toStringNoCache();
    }
    return _toString;
  }
method to obtain ClientProxyMembership for client side
geode-core/src/main/java/org/apache/geode/internal/cache/tier/sockets/ClientProxyMembershipID.java