while ((line = reader.readLine()) != null) {
                // Remove comments
                final String replacedLine = line.replaceAll("#.*$", StringUtil.EMPTY).trim();

                // Skip empty lines or comment lines
                if (replacedLine.length() == 0) {
                    if (updater != null) {
                        updater.write(line);
                    }
                    continue;
                }

It is just a function that can take all the same parameters that a *path operation function* can take:

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[8:9] *}

That's it.

**2 lines**.

And it has the same shape and structure that all your *path operation functions* have.

You can think of it as a *path operation function* without the "decorator" (without the `@app.get("/some-path")`).

# 流式数据 { #stream-data }

如果你要流式传输可以结构化为 JSON 的数据，你应该[流式传输 JSON Lines](../tutorial/stream-json-lines.md)。

但如果你想流式传输纯二进制数据或字符串，可以按下面的方法操作。

/// info | 信息

自 FastAPI 0.134.0 起新增。

///

## 使用场景 { #use-cases }

如果你想流式传输纯字符串，例如直接来自某个 AI LLM 服务的输出，可以使用它。

你也可以用它来流式传输大型二进制文件，在读取的同时按块发送，无需一次性把所有内容读入内存。

你还可以用这种方式流式传输视频或音频，甚至可以在处理的同时生成并发送。

## 使用 `yield` 的 `StreamingResponse` { #a-streamingresponse-with-yield }

대규모 또는 무한 스트림에서는 더욱 중요합니다.

///

/// tip | 팁

`StreamingResponse`를 직접 반환하는 대신, [데이터 스트리밍](./stream-data.md)에서의 스타일을 따르는 것이 더 편리하며 백그라운드에서 취소 처리를 해줍니다.

JSON Lines를 스트리밍한다면, [JSON Lines 스트리밍](../tutorial/stream-json-lines.md) 튜토리얼을 확인하세요.

///

### `FileResponse` { #fileresponse }

파일을 비동기로 스트리밍하여 응답합니다.

다른 응답 유형과는 다른 인수를 사용하여 객체를 생성합니다:

* `path` - 스트리밍할 파일의 경로.

	for {
		line, err := scanner.ReadString('\n')
		if err == io.EOF {
			break
		}

		fields := strings.Fields(line)
		if len(fields) != expectedNumFieldsPerLine {
			// ignore incorrect lines.
			continue
		}

		// Freq should be an integer.
		if _, err := strconv.Atoi(fields[4]); err != nil {
			return nil, err
		}

		// Pass should be an integer.

import java.io.Reader;
import java.util.Iterator;
import java.util.NoSuchElementException;

import org.codelibs.core.exception.ClUnsupportedOperationException;

/**
 * An {@link Iterator} that iterates over lines read from a {@link BufferedReader}.
 * <p>
 * Usage example:
 * </p>
 *
 * <pre>
 * import static org.codelibs.core.io.LineIterator.*;
 *
 * BufferedReader reader = ...;

    * So, by using FastAPI you are saving development time, bugs, lines of code, and you would probably get the same performance (or better) you would if you didn't use it (as you would have to implement it all in your code).

 * JavaScript parser `urltestparser.js` with which this class attempts to be compatible.
 *
 * Each line of the `urltestdata.txt` file specifies a test. Lines look like this:
 *
 * ```
 * http://example\t.\norg http://example.org/foo/bar s:http h:example.org p:/
 * ```
 */
class WebPlatformUrlTestData {
  var input: String? = null
  var base: String? = null

        InputStreamThread thread = jobProcess.getInputStreamThread();
        thread.start();
        thread.join(1000);

        String output = thread.getOutput();
        assertTrue("Should contain recent lines", output.contains("line5"));

        assertTrue("Should have line3", thread.contains("line3"));
        assertTrue("Should have line4", thread.contains("line4"));

                .filter(p -> p.toString().endsWith(".adoc"))
                .forEach(file -> {
                    try {
                        // The regex `^\\s*\\[\\[(.*)\\]\\]` looks for lines starting with '[[...]]'
                        // and captures the content within the brackets.
                        Files.readAllLines(file).forEach(line -> {