private static <T> void setAttributeValue(final LoadBalancer.Subchannel subchannel,
                                              final Attributes.Key<Ref<T>> key,
                                              final Attributes newAttributes) {
        final Ref<T> newValueRef = newAttributes.get(key);
        if (Objects.nonNull(newValueRef)) {
            setAttributeValue(subchannel, key, newValueRef.value);
        }
    }
Set AttributeValue.

@param subchannel    subchannel
@param key           key
@param newAttributes newAttributes
@param <T>           t
shenyu-plugin/shenyu-plugin-proxy/shenyu-plugin-rpc/shenyu-plugin-grpc/src/main/java/org/apache/shenyu/plugin/grpc/loadbalance/SubChannels.java