#### `lru_cache` Technical Details

    ```Python hl_lines="1  10"
    {!> ../../../docs_src/settings/app03/main.py!}
    ```

Dann wird bei allen nachfolgenden Aufrufen von `get_settings()`, in den Abhängigkeiten für darauffolgende Requests, dasselbe Objekt zurückgegeben, das beim ersten Aufruf zurückgegeben wurde, anstatt den Code von `get_settings()` erneut auszuführen und ein neues `Settings`-Objekt zu erstellen.

#### Technische Details zu `lru_cache`

    ```Python hl_lines="1  11"
    {!> ../../../docs_src/settings/app03_an/main.py!}
    ```

=== "Python 3.8+ 非注解版本"

    !!! tip
        如果可能，请尽量使用 `Annotated` 版本。

    ```Python hl_lines="1  10"
    {!> ../../../docs_src/settings/app03/main.py!}
    ```

然后，在下一次请求的依赖项中对 `get_settings()` 进行任何后续调用时，它不会执行 `get_settings()` 的内部代码并创建新的 `Settings` 对象，而是返回在第一次调用时返回的相同对象，一次又一次。

#### `lru_cache` 技术细节

{!../../../docs_src/settings/app02/main.py!}
```

!!! tip
    👥 🔜 🔬 `@lru_cache` 🍖.

    🔜 👆 💪 🤔 `get_settings()` 😐 🔢.

& ⤴️ 👥 💪 🚚 ⚫️ ⚪️➡️ *➡ 🛠️ 🔢* 🔗 & ⚙️ ⚫️ 🙆 👥 💪 ⚫️.

```Python hl_lines="16  18-20"
{!../../../docs_src/settings/app02/main.py!}
```

### ⚒ & 🔬

⤴️ ⚫️ 🔜 📶 ⏩ 🚚 🎏 ⚒ 🎚 ⏮️ 🔬 🏗 🔗 🔐 `get_settings`:

```Python hl_lines="9-10  13  21"

    @JvmField var data: ByteArray? = null

    @JvmField var settings: Settings? = null

    @JvmField var ack = false

    @JvmField var payload1 = 0

    @JvmField var payload2 = 0

    override fun settings(
      clearPrevious: Boolean,
      settings: Settings,
    ) {
      check(type == -1)
      this.type = Http2.TYPE_SETTINGS
      this.clearPrevious = clearPrevious

    }
  }

  /** Write okhttp's settings to the peer. */
  @Throws(IOException::class)
  fun settings(settings: Settings) {
    this.withLock {
      if (closed) throw IOException("closed")
      frameHeader(
        streamId = 0,
        length = settings.size() * 6,
        type = TYPE_SETTINGS,
        flags = FLAG_NONE,
      )
      for (i in 0 until Settings.COUNT) {
        if (!settings.isSet(i)) continue

    assertThat(ackFrame.type).isEqualTo(Http2.TYPE_SETTINGS)
    assertThat(ackFrame.streamId).isEqualTo(0)
    assertThat(ackFrame.ack).isTrue()

    taskFaker.runTasks()

    return connection
  }

  private fun updateMaxConcurrentStreams(
    connection: Http2Connection,
    amount: Int,
  ) {
    val settings = Settings()
    settings[Settings.MAX_CONCURRENT_STREAMS] = amount

          }
        }
    }
  }

  companion object {
    const val OKHTTP_CLIENT_WINDOW_SIZE = 16 * 1024 * 1024

    val DEFAULT_SETTINGS =
      Settings().apply {
        set(Settings.INITIAL_WINDOW_SIZE, DEFAULT_INITIAL_WINDOW_SIZE)
        set(Settings.MAX_FRAME_SIZE, Http2.INITIAL_MAX_FRAME_SIZE)
      }

    const val INTERVAL_PING = 1
    const val DEGRADED_PING = 2

        .pingIntervalMillis(pingIntervalMillis)
        .flowControlListener(flowControlListener)
        .build()
    this.http2Connection = http2Connection
    this.allocationLimit = Http2Connection.DEFAULT_SETTINGS.getMaxConcurrentStreams()
    http2Connection.start()
  }

  /**
   * Returns true if this connection can carry a stream allocation to `address`. If non-null
   * `route` is the resolved route for a connection.

    // Write the mocking script.
    val settings1 = Settings()
    settings1[Settings.HEADER_TABLE_SIZE] = 10000
    settings1[Settings.INITIAL_WINDOW_SIZE] = 20000
    settings1[Settings.MAX_FRAME_SIZE] = 30000
    peer.sendFrame().settings(settings1)
    peer.acceptFrame() // ACK SETTINGS
    val settings2 = Settings()
    settings2[Settings.INITIAL_WINDOW_SIZE] = 40000
    settings2[Settings.MAX_FRAME_SIZE] = 50000