public AesEaxParameters build() throws GeneralSecurityException {
      if (keySizeBytes == null) {
        throw new GeneralSecurityException("Key size is not set");
      }
      if (ivSizeBytes == null) {
        throw new GeneralSecurityException("IV size is not set");
      }
      if (variant == null) {
        throw new GeneralSecurityException("Variant is not set");
      }

      if (tagSizeBytes == null) {
        throw new GeneralSecurityException("Tag size is not set");
      }

      return new AesEaxParameters(keySizeBytes, ivSizeBytes, tagSizeBytes, variant);
    }
The tag size accepts values between 0 and 16 bytes. However, some implementation may not
support the full set of parameters at the moment and may restrict the tag size to a fixed
value (i.e. 16 bytes).
java_src/src/main/java/com/google/crypto/tink/aead/AesEaxParameters.java