On RFC7232-2.3.2, StrongValidator and WeakValidator get different comparison result.
o Strong comparison: two entity-tags are equivalent if both are not weak and their opaque-tags match character-by-character.
o Weak comparison: two entity-tags are equivalent if their opaque-tags match character-by-character, regardless of either or both being tagged as "weak".
But, ShallowEtagHeaderFilter.java always compare the ETag like Weak Comparison even if isWriteWeakETag() is false.
How about adding Validator in ShallowEtagHeaderFilter.java, and using suitable implementation(StrongValidator or WeakValidator)?
Sorry, I worked on old wrong branch, I'll check it again.