}

    /**
     * Validates that a given file is safe and does not attempt path traversal attacks.
     * <p>
     * This is a convenience method that converts File objects to Path and calls
     * {@link #isPathSafe(Path, Path)}.
     * </p>
     *
     * @param fileToCheck the file to validate (must not be {@literal null})
     * @param baseDirectory the base directory that the file must be within (must not be {@literal null})

 * singleton and regular maps respectively. For sorted maps, it's a thin wrapper around {@link
 * java.util.TreeMap}.
 *
 * @see ImmutableSortedMap
 * @author Hayward Chan
 */
public abstract class ImmutableMap<K, V> implements Map<K, V>, Serializable {

  abstract static class IteratorBasedImmutableMap<K, V> extends ImmutableMap<K, V> {

// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package zip

import (
	"bytes"
	"compress/flate"
	"encoding/binary"
	"fmt"
	"hash/crc32"
	"io"
	"io/fs"
	"math/rand"
	"os"
	"strings"
	"testing"
	"testing/fstest"
	"time"
)

// TODO(adg): a more sophisticated test suite

type WriteTest struct {

pkg context, type CancelFunc func()
pkg context, type Context interface { Deadline, Done, Err, Value }
pkg context, type Context interface, Deadline() (time.Time, bool)
pkg context, type Context interface, Done() <-chan struct
pkg context, type Context interface, Err() error
pkg context, type Context interface, Value(interface{}) interface{}
pkg context, var Canceled error
pkg context, var DeadlineExceeded error

  }

  /**
   * Reads a char as specified by {@link DataInputStream#readChar()}, except using little-endian
   * byte order.
   *
   * @return the next two bytes of the input stream, interpreted as a {@code char} in little-endian
   *     byte order
   * @throws IOException if an I/O error occurs
   */
  @CanIgnoreReturnValue // to skip some bytes
  @Override
  public char readChar() throws IOException {

// 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
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//

   * going and grow as needed.
   */
  private static final ThreadLocal<char[]> DEST_TL =
      new ThreadLocal<char[]>() {
        @Override
        protected char[] initialValue() {
          return new char[1024];
        }
      };

This way, you don't have to know beforehand what the valid field/attribute names are (as would be the case with Pydantic models).

This would be useful if you want to receive keys that you don't already know.

---

Another useful case is when you want to have keys of another type (e.g., `int`).

That's what we are going to see here.

	input       chan *queueItem           // input for workers
	queue       chan *queueItem           // output from workers in order
	err         error                     // global error state, only touched by Reader.Read
	bufferPool  bpool.Pool[[]byte]        // pool of []byte objects for input
	kvDstPool   bpool.Pool[[]jstream.KVS] // pool of []jstream.KVS used for output

If there's no `gzip` in the header, it will not try to decompress the body.

That way, the same route class can handle gzip compressed or uncompressed requests.

{* ../../docs_src/custom_request_and_route/tutorial001_an_py310.py hl[9:16] *}

### Create a custom `GzipRoute` class { #create-a-custom-gziproute-class }

Next, we create a custom subclass of `fastapi.routing.APIRoute` that will make use of the `GzipRequest`.