validateApi(body, messages -> {});
        return kuromojiService.getKuromojiFile(body.dictId)
                .map(file -> asStream(new File(file.getPath()).getName()).contentTypeOctetStream().stream(out -> {
                    file.writeOut(out);
                }))
                .orElseGet(() -> {
                    throwValidationErrorApi(messages -> messages.addErrorsFailedToDownloadProtwordsFile(GLOBAL));

        validateApi(body, messages -> {});
        return protwordsService.getProtwordsFile(body.dictId)
                .map(file -> asStream(new File(file.getPath()).getName()).contentTypeOctetStream().stream(out -> {
                    file.writeOut(out);
                }))
                .orElseGet(() -> {
                    throwValidationErrorApi(messages -> messages.addErrorsFailedToDownloadProtwordsFile(GLOBAL));

            }
            // 404
            throw responseManager.new404("Thumbnail for " + form.docId + " is under generating.");
        }

        return asStream(form.docId).contentType(getImageMimeType(thumbnailFile)).stream(out -> {
            try (BufferedInputStream in = new BufferedInputStream(new FileInputStream(thumbnailFile))) {
                out.write(in);
            }
        });
    }

 * Fix: Support Shoutcast HTTP responses like `ICY 200 OK`.
 * Fix: Don't unzip if there isn't a response body.
 * Fix: Don't leak gzip streams on redirects.
 * Fix: Don't do DNS lookups on invalid hosts.
 * Fix: Exhaust the underlying stream when reading gzip streams.
 * Fix: Support the `PATCH` method.
 * Fix: Support request bodies on `DELETE` method.
 * Fix: Drop the `okhttp-protocols` module.

import static java.lang.Double.isNaN;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.util.Iterator;
import java.util.stream.DoubleStream;
import java.util.stream.IntStream;
import java.util.stream.LongStream;

/**
 * A mutable object which accumulates double values and tracks some basic statistics over all the

  /**
   * Copies all bytes from the input stream to the output stream. Does not close or flush either
   * stream.
   *
   * <p><b>Java 9 users and later:</b> this method should be treated as deprecated; use the
   * equivalent {@link InputStream#transferTo} method instead.
   *
   * @param from the input stream to read from
   * @param to the output stream to write to
   * @return the number of bytes copied

- ✅ Failed extraction includes descriptive error messages
- ✅ Null input stream validation
- ✅ Error messages include file type context

---

### 2. FilenameExtractorEnhancedTest.java
**Purpose**: Test FilenameExtractor edge cases and new documentation.

**Key Test Areas**:
- Parameter handling (null, empty, missing)
- Special character handling
- Input stream validation (not consumption)
- Edge cases (long filenames, paths, whitespace)

        validateApi(body, messages -> {});
        return synonymService.getSynonymFile(body.dictId)
                .map(file -> asStream(new File(file.getPath()).getName()).contentTypeOctetStream().stream(out -> {
                    file.writeOut(out);
                }))
                .orElseGet(() -> {
                    throwValidationErrorApi(messages -> messages.addErrorsFailedToDownloadProtwordsFile(GLOBAL));

	start := time.Now()
	stream, err := handler.Call(t.Context(), remoteConn, &testRequest{Num: 1, String: testPayload})
	errFatal(err)
	go func() {
		defer close(stream.Requests)
		for i := range payloads {
			// t.Log("sending new client request")
			stream.Requests <- &testRequest{Num: i, String: testPayload}
		}
	}()
	var n int
	err = stream.Results(func(resp *testResponse) error {

        validateApi(body, messages -> {});
        return stopwordsService.getStopwordsFile(body.dictId)
                .map(file -> asStream(new File(file.getPath()).getName()).contentTypeOctetStream().stream(out -> {
                    file.writeOut(out);
                }))
                .orElseGet(() -> {
                    throwValidationErrorApi(messages -> messages.addErrorsFailedToDownloadStopwordsFile(GLOBAL));