* [trailers], this doesn't block if the trailers are not immediately available, and instead
   * returns null.
   *
   * This will typically return null until [ResponseBody.source] has buffered the last byte of the
   * response body. Call `body.source().request(1024 * 1024)` to block until either that's done, or
   * 1 MiB of response data is loaded into memory. (You could use any size here, though large values

    testRotate(new byte[] {0, 1, 2, 3, 4, 5, 6}, 1, 0, 3, new byte[] {2, 0, 1, 3, 4, 5, 6});
    testRotate(new byte[] {0, 1, 2, 3, 4, 5, 6}, 2, 0, 3, new byte[] {1, 2, 0, 3, 4, 5, 6});

    // Rotate the last four elements
    testRotate(new byte[] {0, 1, 2, 3, 4, 5, 6}, -6, 3, 7, new byte[] {0, 1, 2, 5, 6, 3, 4});
    testRotate(new byte[] {0, 1, 2, 3, 4, 5, 6}, -5, 3, 7, new byte[] {0, 1, 2, 4, 5, 6, 3});

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful

     * then set the result of the computation, and only then transition to COMPLETED, CANCELLED, or
     * INTERRUPTED.
     *
     * <p>We don't use the integer argument passed between acquire methods so we pass around a -1
     * everywhere.
     */
    static final class Sync<V> extends AbstractQueuedSynchronizer {

      private static final long serialVersionUID = 0L;

      /* Valid states. */

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful

                }

                @Override
                public FileVisitResult postVisitDirectory(Path dir, IOException exc) throws IOException {
                    // Go up one package by jumping back to the second to last '.'
                    packageName = packageName.substring(0, 1 + packageName.lastIndexOf('.', packageName.length() - 2));
                    return FileVisitResult.CONTINUE;
                }

                @Override

与其他响应类型相比，接受不同的参数集进行实例化：

* `path` - 要流式传输的文件的文件路径。
* `headers` - 任何自定义响应头，传入字典类型。
* `media_type` - 给出媒体类型的字符串。如果未设置，则文件名或路径将用于推断媒体类型。
* `filename` - 如果给出，它将包含在响应的 `Content-Disposition` 中。

文件响应将包含适当的 `Content-Length`、`Last-Modified` 和 `ETag` 响应头。

{* ../../docs_src/custom_response/tutorial009_py310.py hl[2,10] *}

你也可以使用 `response_class` 参数：

{* ../../docs_src/custom_response/tutorial009b_py310.py hl[2,8,10] *}

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful

            },
        ),
      )
    val response = call.execute()
    assertThat(response.body.string()).isEqualTo("ABCDE")
    val request = server.takeRequest()
    assertThat(request.requestLine).isEqualTo("POST /foo HTTP/2")
    assertArrayEquals(postBytes, request.body?.toByteArray())
    assertThat(request.headers["Content-Length"]).isNull()
  }

  @Test
  fun userSuppliedContentLengthHeader() {