* change its working directly concurrently with a call to deleteDirectoryContents?), it makes
       * more sense for us to fall back to a generic FileSystemException (by returning null here)
       * than to dereference parentPath and end up producing NullPointerException.
       */
      return null;
    }
    // requireNonNull is safe because paths have file names when they have parents.

# CL 153420045 crypto/x509: continue to recognise MaxPathLen of zero as "no value"., Adam Langley <******@****.***>
pkg crypto/x509, type Certificate struct, MaxPathLenZero bool

# CL 158950043 database/sql: add Drivers, returning list of registered drivers, Russ Cox <******@****.***>
pkg database/sql, func Drivers() []string

# CL 117280043 debug/dwarf: fix Reader panic on DW_TAG_unspecified_type, Derek Parker <******@****.***>

///

## Renvoyer une `Response` personnalisée { #returning-a-custom-response }

    ListeningExecutorService service = listeningDecorator(newDirectExecutorService());
    assertThat(listeningDecorator(service)).isSameInstanceAs(service);
    List<Callable<String>> callables = ImmutableList.of(Callables.returning("x"));
    List<Future<String>> results;

    results = service.invokeAll(callables);
    assertThat(getOnlyElement(results)).isInstanceOf(TrustedListenableFutureTask.class);

    ListeningExecutorService service = listeningDecorator(newDirectExecutorService());
    assertThat(listeningDecorator(service)).isSameInstanceAs(service);
    List<Callable<String>> callables = ImmutableList.of(Callables.returning("x"));
    List<Future<String>> results;

    results = service.invokeAll(callables);
    assertThat(getOnlyElement(results)).isInstanceOf(TrustedListenableFutureTask.class);

   *
   * <p>When the weight of an entry is zero it will not be considered for size-based eviction
   * (though it still may be evicted by other means).
   *
   * <p><b>Important note:</b> Instead of returning this as a {@code CacheBuilder}
   * instance, this method returns {@code CacheBuilder<K1, V1>}. From this point on, either the
   * original reference or the returned reference may be used to complete configuration and build

/// note | 技術細節

你也可以使用 `from starlette.responses import JSONResponse`。

**FastAPI** 為了方便開發者，將 `starlette.responses` 也提供為 `fastapi.responses`。但大多數可用的回應類型其實直接來自 Starlette。

///

## 回傳自訂 `Response` { #returning-a-custom-response }

上面的範例展示了所需的各個部分，但目前還不太實用，因為你其實可以直接回傳 `item`，**FastAPI** 就會幫你把它放進 `JSONResponse`，轉成 `dict` 等，這些都是預設行為。

現在來看看如何用它來回傳自訂回應。

假設你想要回傳一個 [XML](https://en.wikipedia.org/wiki/XML) 回應。

     */
    protected String renderMarkdownToHtml(final String markdown) {
        if (markdownRenderer == null || !markdownRenderer.isInitialized()) {
            logger.warn("MarkdownRenderer is not initialized, returning escaped text");
            return escapeHtml(markdown);
        }
        return markdownRenderer.render(markdown);
    }

    /**
     * Escapes HTML special characters.
     *

    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(2, 3, 4, 5, 6, 7, 8, 9, 0);

    // get(K, Callable) doesn't stop 2 from expiring
    Integer unused = cache.get(2, Callables.returning(-2));
    CacheTesting.drainRecencyQueues(cache);
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(3, 4, 5, 6, 7, 8, 9, 0);

    // asMap.put saves 3
    cache.asMap().put(3, -3);

  private abstract static class RawTypeConsistencyTester<T extends Enum<T> & CharSequence> {
    abstract T returningT();

    abstract void acceptT(T t);

    abstract <X extends T> X returningX();

    abstract <X> void acceptX(X x);

    abstract <T2 extends Enum<T2> & CharSequence> T2 returningT2();

    abstract <T2 extends CharSequence & Iterable<T2>> void acceptT2(T2 t2);