public static void testFileEncryption(StreamingAead ags, File tmpFile, int plaintextSize)
      throws Exception {
    testFileEncryptionWithChannel(ags, tmpFile, plaintextSize);
    testFileEncryptionWithStream(ags, tmpFile, plaintextSize);
  }
Encrypts some plaintext to a file using FileOutputStream, then decrypt with a FileInputStream.
Reading and writing is done byte by byte.
java_src/src/main/java/com/google/crypto/tink/testing/StreamingTestUtil.java