@CanIgnoreReturnValue
    public Builder setVariant(Variant variant) {
      this.variant = variant;
      return this;
    }
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