+ " GraphBuilder)")
public abstract class Traverser<N> {
  private final SuccessorsFunction<N> successorFunction;

  private Traverser(SuccessorsFunction<N> successorFunction) {
    this.successorFunction = checkNotNull(successorFunction);
  }

  /**
   * Creates a new traverser for the given general {@code graph}.
   *
   * <p>Traversers created using this method are guaranteed to visit each node reachable from the

    return checkNotNull(iterable);
  }

  /**
   * Returns a fluent iterable that combines two iterables. The returned iterable has an iterator
   * that traverses the elements in {@code a}, followed by the elements in {@code b}. The source
   * iterators are not polled until necessary.
   *
   * <p>The returned iterable's iterator supports {@code remove()} when the corresponding input

    return checkNotNull(iterable);
  }

  /**
   * Returns a fluent iterable that combines two iterables. The returned iterable has an iterator
   * that traverses the elements in {@code a}, followed by the elements in {@code b}. The source
   * iterators are not polled until necessary.
   *
   * <p>The returned iterable's iterator supports {@code remove()} when the corresponding input

   */
  private static <N> Iterable<N> getReachableNodes(
      Graph<N> graph, N node, TransitiveClosureSelfLoopStrategy strategy) {
    Traverser<N> traverser = Traverser.forGraph(graph);
    switch (strategy) {
      case ADD_SELF_LOOPS_ALWAYS: // always include 'node'
        return traverser.breadthFirst(node);
      case ADD_SELF_LOOPS_FOR_CYCLES: // include 'node' iff there's an incident cycle

    return cycle(Lists.newArrayList(elements));
  }

  /**
   * Combines two iterables into a single iterable. The returned iterable has an iterator that
   * traverses the elements in {@code a}, followed by the elements in {@code b}. The source
   * iterators are not polled until necessary.
   *
   * <p>The returned iterable's iterator supports {@code remove()} when the corresponding input

      return backingMap.isEmpty();
    }

    @Override
    public void clear() {
      backingMap.clear();
    }
  }

  /**
   * {@inheritDoc}
   *
   * <p>The set's iterator traverses the mappings for the first row, the mappings for the second
   * row, and so on.
   *
   * <p>Each cell is an immutable snapshot of a row key / column key / value mapping, taken at the

 *
 * <p>This class and its iterator implement all of the optional methods of the {@link
 * Collection} and {@link Iterator} interfaces. The Iterator provided in method {@link #iterator()}
 * is not guaranteed to traverse the elements of the MonitorBasedPriorityBlockingQueue in
 * any particular order. If you need ordered traversal, consider using {@code
 * Arrays.sort(pq.toArray())}. Also, method {@code drainTo} can be used to remove some or

    }

    /**
     * Recursively scan the given directory, adding resources for each file encountered. Symlinks
     * which have already been traversed in the current tree path will be skipped to eliminate
     * cycles; otherwise symlinks are traversed.
     *
     * @param directory the root of the directory to scan
     * @param packagePrefix resource path prefix inside {@code classloader} for any files found

  }

  /**
   * Returns an unmodifiable set of all row key / column key / value triplets. Changes to the table
   * will update the returned set.
   *
   * <p>The returned set's iterator traverses the mappings with the first row key, the mappings with
   * the second row key, and so on.
   *
   * <p>The value in the returned cells may change if the table subsequently changes.
   *

        baseDir.mkdirs();
        File maliciousFile = new File(baseDir, "a/b/c/../../../../../tmp/evil");

        Boolean result = invokeIsValidUploadPath(maliciousFile, baseDir);
        assertFalse("Multiple path traversals should be blocked", result);
    }

    @Test
    public void test_isValidUploadPath_edgeCase_sameDirectory() throws Exception {
        // Test file directly in base directory