* simultaneously adopted and removed.
   */
  private val connections = ConcurrentLinkedQueue<RealConnection>()

  init {
    // Put a floor on the keep alive duration, otherwise cleanup will spin loop.
    require(keepAliveDuration > 0L) { "keepAliveDuration <= 0: $keepAliveDuration" }
  }

  fun idleConnectionCount(): Int =
    connections.count {

        Object newValue = new Object();
        assertSame(entry.getValue(), cache.asMap().put(entry.getKey(), newValue));
        // don't let the new entry get GCed
        warmed.add(entryOf(entry.getKey(), newValue));
        Object newKey = new Object();
        assertNull(cache.asMap().put(newKey, entry.getValue()));
        // this getUnchecked() call shouldn't be a cache miss; verified below

Mientras construyes una API, el "path" es la forma principal de separar "concerns" y "resources".

#### Operación

"Operación" aquí se refiere a uno de los "métodos" HTTP.

Uno de:

* `POST`
* `GET`
* `PUT`
* `DELETE`

...y los más exóticos:

* `OPTIONS`
* `HEAD`
* `PATCH`
* `TRACE`

En el protocolo HTTP, puedes comunicarte con cada path usando uno (o más) de estos "métodos".

---

#### Toán tử (Operation)

"Toán tử" ở đây được nhắc tới là một trong các "phương thức" HTTP.

Một trong những:

* `POST`
* `GET`
* `PUT`
* `DELETE`

...và một trong những cái còn lại:

* `OPTIONS`
* `HEAD`
* `PATCH`
* `TRACE`

    public boolean containsKey(@Nullable Object key) {
      return rangeContains(key) && super.containsKey(key);
    }

    @Override
    public @Nullable V put(C key, V value) {
      checkArgument(rangeContains(checkNotNull(key)));
      return super.put(key, value);
    }
  }

  /** Overridden column iterator to return columns values in globally sorted order. */
  @Override
  Iterator<C> createColumnKeyIterator() {

 * parameters with actual credentials.
 *
 * <p>Usage example:
 * <pre>
 * {@code
 * Map<String, String> params = new HashMap<>();
 * params.put("token_url", "http://example.com/token");
 * params.put("login_url", "http://example.com/login");
 * FormScheme formScheme = new FormScheme(params);
 * formScheme.authenticate(credentials, executor);
 * }
 * </pre>
 *
 * <p>Parameters:
 * <ul>

    if (!isSelfLoop) {
      addOutEdge(edge, node);
    }
  }

  @Override
  public void addOutEdge(E edge, N node) {
    N previousNode = incidentEdgeMap.put(edge, node);
    checkState(previousNode == null);
  }

         * name as a zero terminated ascii string "\TMP" + '\0'
         *
         * As is this works, but it deviates from the spec section 4.1.6.6 but
         * maybe I should put it in. Wonder what NT does?
         */

        return dstIndex - start;
    }

    @Override
    int writeDataWireFormat(final byte[] dst, final int dstIndex) {
        return 0;
    }

    @Override

            if (pair == null) {
                pair = new Pair<>(new HashMap<>(), new ArrayList<>());
                relatedContentMap.put(key, pair);
            }
            if (entity.getTerm().startsWith(regexPrefix)) {
                final String regex = entity.getTerm().substring(regexPrefix.length());
                if (StringUtil.isBlank(regex)) {

  fun run() {
    fileSystem.write(path) {
      writeUtf8("{}")
    }

    val request =
      Request
        .Builder()
        .url("https://httpbin.org/anything")
        .put(path.asRequestBody(fileSystem, MEDIA_TYPE_JSON))
        .build()

    client.newCall(request).execute().use { response ->
      if (!response.isSuccessful) throw IOException("Unexpected code $response")