@Override
  public String toString() {
    return "AesGcmHkdfStreaming Parameters (IKM size: "
        + keySizeBytes
        + ", "
        + derivedAesGcmKeySizeBytes
        + "-byte AES GCM key, "
        + hkdfHashType
        + " for HKDF "
        + ciphertextSegmentSizeBytes
        + "-byte ciphertexts)";
  }
Returns the size a ciphertext segment has.
java_src/src/main/java/com/google/crypto/tink/streamingaead/AesGcmHkdfStreamingParameters.java