public DynamicEndpointGroup build() {
        if (selectionStrategy != null) {
            return new DynamicEndpointGroup(selectionStrategy, shouldAllowEmptyEndpoints(),
                                            selectionTimeoutMillis());
        }
        return new DynamicEndpointGroup(shouldAllowEmptyEndpoints());
    }
Returns a newly created {@link DynamicEndpointGroup} with the properties configured so far.
core/src/main/java/com/linecorp/armeria/client/endpoint/DynamicEndpointGroupBuilder.java