But before that, handling asynchronous code was quite more complex and difficult.

In previous versions of Python, you could have used threads or <a href="https://www.gevent.org/" class="external-link" target="_blank">Gevent</a>. But the code is way more complex to understand, debug, and think about.

     *
     * @param manager channel manager
     */
    public ChannelFailover(ChannelManager manager) {
        this.manager = manager;
        this.executor = Executors.newCachedThreadPool(r -> {
            Thread t = new Thread(r, "MultiChannelFailover");
            t.setDaemon(true);
            return t;
        });
        this.failoverStates = new ConcurrentHashMap<>();
    }

    /**
     * Handle channel failure
     *

   * {@code directExecutor} functions should avoid heavyweight operations inside {@code
   * AsyncFunction.apply}. Any heavyweight operations should occur in other threads responsible for
   * completing the returned {@code Future}.)
   *
   * <p>This method is similar to {@link java.util.concurrent.CompletableFuture#exceptionally}. It

 * evicted or manually invalidated. The common way to build instances is using {@link CacheBuilder}.
 *
 * <p>Implementations of this interface are expected to be thread-safe, and can be safely accessed
 * by multiple concurrent threads.
 *
 * @param <K> the type of the cache's keys, which are not permitted to be null
 * @param <V> the type of the cache's values, which are not permitted to be null
 * @author Charles Fry

    }

    public void test_thread_priority_settings() {
        // Test basic priority configurations without creating threads
        dataIndexHelper.setCrawlerPriority(Thread.MIN_PRIORITY);
        dataIndexHelper.setCrawlerPriority(Thread.NORM_PRIORITY);
        dataIndexHelper.setCrawlerPriority(Thread.MAX_PRIORITY);
        assertTrue("Priority settings should be fast", true);
    }

Mas antes disso, controlar código assíncrono era bem mais complexo e difícil.

Nas versões anteriores do Python, você poderia utilizar threads ou <a href="http://www.gevent.org/" class="external-link" target="_blank">Gevent</a>. Mas o código é bem mais complexo de entender, debugar, e pensar sobre.

     * as well as to handle state changes in a thread-safe manner. The current state of the future
     * is held in the Sync state, and the lock is released whenever the state changes to {@link
     * #COMPLETED}, {@link #CANCELLED}, or {@link #INTERRUPTED}
     *
     * <p>To avoid races between threads doing release and acquire, we transition to the final state

 * example involving two locks and two threads, deadlock occurs when one thread acquires Lock A, and
 * then Lock B, while another thread acquires Lock B, and then Lock A:
 *
 * <pre>
 * Thread1: acquire(LockA) --X acquire(LockB)
 * Thread2: acquire(LockB) --X acquire(LockA)
 * </pre>
 *
 * <p>Neither thread will progress because each is waiting for the other. In more complex

labels.includedUrls=Included URLs for Crawling
labels.includedDocPaths=Included Paths for Searching
labels.includedDocUrls=Included URLs for Searching
labels.maxAccessCount=Max Access Count
labels.name=Name
labels.numOfThread=Number of Threads
labels.duplicateHostName=Duplicate Host Name
labels.pageNumber=Page Number
labels.password=Password
labels.paths=Paths
labels.port=Port
labels.regex=Regex
labels.regularName=Regular Name

      --enable-gnu-unique-object \
      --enable-initfini-array \
      --enable-languages="c,c++" \
      --enable-linker-build-id \
      --enable-plugin \
      --enable-shared \
      --enable-threads=posix \
      --with-default-libstdcxx-abi=${LIBSTDCXX_ABI} \
      --with-gcc-major-version-only \
      --with-linker-hash-style="gnu" \
      && \
      make -j$(nproc) && \
      make install