///

## Password hashing { #password-hashing }

"Hashing" means converting some content (a password in this case) into a sequence of bytes (just a string) that looks like gibberish.

Whenever you pass exactly the same content (exactly the same password) you get exactly the same gibberish.

But you cannot convert from the gibberish back to the password.

    ByteSource source = out.asByteSource();
    int chunk1 = min(dataSize, fileThreshold);
    int chunk2 = dataSize - chunk1;

    // Write just enough to not trip the threshold
    if (chunk1 > 0) {
      write(out, data, 0, chunk1, singleByte);
      assertTrue(ByteSource.wrap(data).slice(0, chunk1).contentEquals(source));
    }
    File file = out.getFile();

    return (Collector) ONLY_ELEMENT;
  }

  /**
   * This atrocity is here to let us report several of the elements in the stream if there were more
   * than one, not just two.
   */
  @SuppressWarnings("EmptyList") // ImmutableList doesn't support nullable element types
  private static final class ToOptionalState {
    static final int MAX_EXTRAS = 4;

    @Nullable Object element;

   * nullness analysis might not understand that the field has been populated. To avoid that problem
   * without having to add {@code @SuppressWarnings}, the code can call this method.
   *
   * <p>Why <i>not</i> just add {@code SuppressWarnings}? The problem is that this method is
   * typically useful for {@code return} statements. That leaves the code with two options: Either

                    logger.warn(msg, e);
                } else {
                    logger.warn(msg);
                }
            }
        }

        // if it already exists locally we were just trying to force it - ignore the update
        if (!artifact.getFile().exists()) {
            if (tfe != null) {
                throw tfe;
            } else {

    public void test_register_arrayList() {
        RenderData data = new RenderData();

        BsUser entity1 = new BsUser();
        entity1.setName("user1");

        // Test ArrayList specifically (not just List interface)
        ArrayList<BsUser> arrayList = new ArrayList<>();
        arrayList.add(entity1);

        RenderDataUtil.register(data, "arrayList", arrayList);

    .url("https://www.nytimes.com/")
    .build();
client.newCall(newYorkTimesRequest).enqueue(new Callback() {
  ...
});
```

Running this race over home WiFi shows the Times (`0002`) completes just slightly sooner than the Post (`0001`):

```
0001 https://www.washingtonpost.com/
0001 0.000 callStart
0002 https://www.nytimes.com/
0002 0.000 callStart
0002 0.010 dnsStart
0001 0.013 dnsStart

But in most of the cases where we need to do something like this, we want the model just to **filter/remove** some of the data as in this example.

Try to find the good side. In general, if people are not being unfriendly, try to thank their effort and interest, even if you disagree with the main subject (discussion, PR), just thank them for being interested in the project, or for having dedicated some time to try to do something.

It's difficult to convey emotion in text, use emojis to help. 😅

    // If we have room for all of it, this is easy
    if (readBuffer.remaining() <= buffer.remaining()) {
      buffer.put(readBuffer);
      munchIfFull();
      return this;
    }

    // First add just enough to fill buffer size, and munch that
    int bytesToCopy = bufferSize - buffer.position();
    for (int i = 0; i < bytesToCopy; i++) {
      buffer.put(readBuffer.get());
    }