new CountDownLatch(1).await(); // the interrupt will wake us up
            } catch (InterruptedException ie) {
              // continue
            }
            LockSupport.unpark(Thread.currentThread()); // simulate a spurious wakeup.
            return null;
          }

          @Override
          boolean isDone() {
            return false;
          }

          @Override

    }

    /**
     * コンテキストクラスローダを返します。
     *
     * @return コンテキストクラスローダ
     */
    public static ClassLoader getClassLoader() {
        return Thread.currentThread().getContextClassLoader();
    }

    /**
     * コンテキストクラスローダからリソースを返します。
     *
     * @param path
     *            リソースのパス。{@literal null}や空文字列であってはいけません
     * @return リソースの{@link URL}

        } catch (final Exception e) {
            throw new ExtractException(e);
        }
    }

    protected XPathAPI getXPathAPI() {
        try {
            return xpathAPICache.get(Thread.currentThread().getName());
        } catch (final ExecutionException e) {
            if (logger.isDebugEnabled()) {
                logger.debug("Failed to retrieval a cache.", e);
            }
            return new XPathAPI();

        // start
        AccessTimeoutTarget accessTimeoutTarget = null;
        TimeoutTask accessTimeoutTask = null;
        if (accessTimeout != null) {
            accessTimeoutTarget = new AccessTimeoutTarget(Thread.currentThread());
            accessTimeoutTask = TimeoutManager.getInstance().addTimeoutTarget(accessTimeoutTarget, accessTimeout, false);
        }

        final ExtractData data = new ExtractData();

            log.trace("Acquire tree " + usage + " " + this);
        }

        if ( track && this.traceResource ) {
            synchronized ( this.acquires ) {
                this.acquires.add(truncateTrace(Thread.currentThread().getStackTrace()));
            }
        }

        if ( usage == 1 ) {
            synchronized ( this ) {
                if ( this.sessionAcquired.compareAndSet(false, true) ) {

  // e.g. Optional<URL> tryGetResource or boolean resourceExists
  public static URL getResource(String resourceName) {
    ClassLoader loader =
        MoreObjects.firstNonNull(
            Thread.currentThread().getContextClassLoader(), Resources.class.getClassLoader());
    URL url = loader.getResource(resourceName);
    checkArgument(url != null, "resource %s not found.", resourceName);
    return url;
  }

  /**

        // start
        AccessTimeoutTarget accessTimeoutTarget = null;
        TimeoutTask accessTimeoutTask = null;
        if (accessTimeout != null) {
            accessTimeoutTarget = new AccessTimeoutTarget(Thread.currentThread());
            accessTimeoutTask = TimeoutManager.getInstance().addTimeoutTarget(accessTimeoutTarget, accessTimeout, false);
        }

        try {
            return getResponseData(uri, includeContent);

        buf.append(",\"event.dataset\":\"").append(ecsEventDataset).append('"');
        buf.append(",\"process.thread.name\":\"").append(StringEscapeUtils.escapeJson(Thread.currentThread().getName())).append('"');
        buf.append(",\"log.logger\":\"").append(StringEscapeUtils.escapeJson(this.getClass().getName())).append('"');

                } catch (final Exception e) {
                    exceptionSet.add(e);
                } finally {
                    done.set(true);
                }
            }, Thread.currentThread().getName() + "-pdf");
            task.setDaemon(isDaemonThread);
            task.start();
            task.join(timeout);
            if (!done.get()) {
                for (int i = 0; i < 100 && !done.get(); i++) {

        // is returned to the delegate Executor interrupted so that it may handle the
        // interruption if it likes.
        if (interruptedDuringTask) {
          Thread.currentThread().interrupt();
        }
      }
    }

    @SuppressWarnings("GuardedBy")
    @Override
    public String toString() {
      Runnable currentlyRunning = task;
      if (currentlyRunning != null) {