assertTrue(unmod.descendingSet().contains(4));

    ensureNotDirectlyModifiable(unmod);
    ensureNotDirectlyModifiable(unmod.descendingSet());
    ensureNotDirectlyModifiable(unmod.headSet(2));
    ensureNotDirectlyModifiable(unmod.headSet(2, true));
    ensureNotDirectlyModifiable(unmod.tailSet(2));
    ensureNotDirectlyModifiable(unmod.tailSet(2, true));
    ensureNotDirectlyModifiable(unmod.subSet(1, 3));

    assertEquals("a", elementSet.first());
    assertEquals("c", elementSet.last());
    assertEquals(Ordering.natural(), elementSet.comparator());

    assertThat(elementSet.headSet("b")).containsExactly("a");
    assertThat(elementSet.tailSet("b")).containsExactly("b", "c").inOrder();
    assertThat(elementSet.subSet("a", "c")).containsExactly("a", "b").inOrder();
  }

    SortedSet<E> createSubSet(SortedSet<E> set, E firstExclusive, E lastExclusive) {
      if (from == Bound.NO_BOUND && to == Bound.EXCLUSIVE) {
        return set.headSet(lastExclusive);
      } else if (from == Bound.INCLUSIVE && to == Bound.NO_BOUND) {
        return set.tailSet(firstInclusive);
      } else if (from == Bound.INCLUSIVE && to == Bound.EXCLUSIVE) {

    assertSame("foo", sortedTable.rowKeySet().last());
  }

  public void testRowKeySetHeadSet() {
    sortedTable = create("foo", 1, 'a', "bar", 1, 'b', "foo", 3, 'c');
    Set<String> set = sortedTable.rowKeySet().headSet("cat");
    assertEquals(singleton("bar"), set);
    set.clear();
    assertTrue(set.isEmpty());
    assertEquals(singleton("foo"), sortedTable.rowKeySet());
  }

  public void testRowKeySetTailSet() {

var SSECopy = ssecCopy{}

type ssecCopy struct{}

// IsRequested returns true if the HTTP headers contains
// at least one SSE-C copy header. Regular SSE-C headers
// are ignored.
func (ssecCopy) IsRequested(h http.Header) bool {
	if _, ok := h[xhttp.AmzServerSideEncryptionCopyCustomerAlgorithm]; ok {
		return true
	}
	if _, ok := h[xhttp.AmzServerSideEncryptionCopyCustomerKey]; ok {
		return true

 * limitations under the License.
 */
package okhttp3.internal.http2

import okio.ByteString
import okio.ByteString.Companion.encodeUtf8

/** HTTP header: the name is an ASCII string, but the value can be UTF-8. */
data class Header(
  /** Name in case-insensitive ASCII encoding. */
  @JvmField val name: ByteString,
  /** Value in UTF-8 encoding. */
  @JvmField val value: ByteString,
) {

# Header-Parameter

So wie `Query`-, `Path`-, und `Cookie`-Parameter können Sie auch <abbr title='Header – Kopfzeilen, Header, Header-Felder: Schlüssel-Wert-Metadaten, die vom Client beim Request, und vom Server bei der Response gesendet werden'>Header</abbr>-Parameter definieren.

## `Header` importieren

Importieren Sie zuerst `Header`:

//// tab | Python 3.10+

```Python hl_lines="3"
{!> ../../docs_src/header_params/tutorial001_an_py310.py!}
```

```

////

/// note | "技术细节"

`Header` 是 `Path`、`Query`、`Cookie` 的**兄弟类**，都继承自共用的 `Param` 类。

注意，从 `fastapi` 导入的 `Query`、`Path`、`Header` 等对象，实际上是返回特殊类的函数。

///

/// info | "说明"

必须使用 `Header` 声明 header 参数，否则该参数会被解释为查询参数。

///

## 自动转换

`Header` 比 `Path`、`Query` 和 `Cookie` 提供了更多功能。

大部分标准请求头用**连字符**分隔，即**减号**（`-`）。

# Header-параметры

Вы можете определить параметры заголовка таким же образом, как вы определяете параметры `Query`, `Path` и `Cookie`.

## Импорт `Header`

Сперва импортируйте `Header`:

//// tab | Python 3.10+

```Python hl_lines="3"
{!> ../../docs_src/header_params/tutorial001_an_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="3"
{!> ../../docs_src/header_params/tutorial001_an_py39.py!}
```

<%@page pageEncoding="UTF-8" contentType="text/html; charset=UTF-8"%>
<la:form action="/search" method="get" styleId="searchForm"
	role="search">
	${fe:facetForm()}${fe:geoForm()}
	<header>
		<nav class="navbar navbar-expand-md navbar-dark fixed-top bg-dark">
			<div id="content" class="container">
				<la:link styleClass="navbar-brand d-inline-flex" href="/">
					<img src="${fe:url('/images/logo-head.png')}"