* quickly, since the row key is provided. However, {@code column(columnKey).size()} takes longer,
 * since an iteration across all row keys occurs.
 *
 * <p>Because a {@code TreeBasedTable} has unique sorted values for a given row, both {@code
 * row(rowKey)} and {@code rowMap().get(rowKey)} are {@link SortedMap} instances, instead of the

 * specified the JVM flag {@code -XX:+DisableExplicitGC}. But in practice, it works very well for
 * ordinary tests.
 *
 * <p>Failure of the expected event to occur within an implementation-defined "reasonable" time
 * period or an interrupt while waiting for the expected event will result in a {@link
 * RuntimeException}.
 *
 * <p>Here's an example that tests a {@code finalize} method:

    awaitTermination(t, LONG_DELAY_MS);
  }

  // Some convenient Runnable classes

  // These classes don't merely allow checked exceptions but also store any exceptions that occur
  // so that we can then report them during tearDown.

  abstract class CheckedRunnable implements Runnable {
    abstract void realRun() throws Throwable;

    @Override
    public final void run() {

     * required to use SMB URLs with the <code>java.net.URL</code> class. If this
     * method is not called before attempting to create an SMB URL with the
     * URL class the following exception will occur:
     * <blockquote>
     *
     * <pre>
     * Exception MalformedURLException: unknown protocol: smb
     *     at java.net.URL.&lt;init&gt;(URL.java:480)
     *     at java.net.URL.&lt;init&gt;(URL.java:376)

                emptyIterator.next();
                count++;
                if (count > 10)
                    break; // Safety check
            }
            assertEquals(0, count, "No iterations should occur for empty iterator");
        }, "EmptyIterator should work with manual iteration");
    }

    @Test
    @DisplayName("EmptyIterator should handle concurrent access safely")

        }
    }

    /**
     * Opens a connection to the specified URL.
     *
     * @param u the URL
     * @return the HttpURLConnection
     * @throws IOException if an I/O exception occurs
     */
    protected HttpURLConnection open(final URL u) throws IOException {
        final HttpURLConnection connection = (HttpURLConnection) (proxy != null ? u.openConnection(proxy) : u.openConnection());

   * colliding threads.  Because search is random, and collisions
   * only become known via CAS failures, convergence can be slow,
   * and because threads are typically not bound to CPUS forever,
   * may not occur at all. However, despite these limitations,
   * observed contention rates are typically low in these cases.
   *
   * It is possible for a Cell to become unused when threads that

     * @param si the starting index in the source array
     * @param slim the limit index in the source array
     * @return the decoded String
     * @throws IOException if a decoding error occurs
     */
    public static String dec_utf8(final byte[] src, int si, final int slim) throws IOException {
        final char[] uni = new char[slim - si];
        int ui, ch;

Job status can also be viewed in a browser by navigating to the YARN ResourceManager Web UI and clicking on job history server information.

### **4.2 WordCount**

WordCount is a simple program that counts how often a word occurs in a text file. The code builds a dataset of (String, Int) pairs called counts, and saves the dataset to a file.

                    for (int j = 0; j < urlsPerThread; j++) {
                        // Access is synchronized internally in the actual implementation
                        // Here we just verify no concurrent modification exceptions occur
                        String url = "http://example.com/thread" + threadIndex + "/doc" + j;
                        // Simulate the synchronized access that happens in deleteDocument()