static <T, U, V, W> Attributes of(AttributeKey<T> k1, T v1,
                                      AttributeKey<U> k2, U v2,
                                      AttributeKey<V> k3, V v3,
                                      AttributeKey<W> k4, W v4) {
        return builder().set(k1, v1)
                        .set(k2, v2)
                        .set(k3, v3)
                        .set(k4, v4)
                        .build();
    }
Returns a new {@link Attributes} with the specified pairs of an {@link AttributeKey} and a {@code value}.
core/src/main/java/com/linecorp/armeria/common/Attributes.java