Iterator<String> keyIterator = keys.iterator();
    keyIterator.next();
    keyIterator.remove();
    assertFalse(underlying.containsKey("c"));

    Collection<String> values = map.values();
    values.remove("4");
    assertFalse(underlying.containsKey("d"));

    Iterator<String> valueIterator = values.iterator();
    valueIterator.next();
    valueIterator.remove();
    assertFalse(underlying.containsKey("e"));

    Iterator<Entry<K, Collection<V>>> entryIterator = unfiltered.asMap().entrySet().iterator();
    boolean changed = false;
    while (entryIterator.hasNext()) {
      Entry<K, Collection<V>> entry = entryIterator.next();
      K key = entry.getKey();
      Collection<V> collection = filterCollection(entry.getValue(), new ValuePredicate(key));
      if (!collection.isEmpty()

            return null;
        }

        ByteBuffer bb = ByteBuffer.wrap(data, offset, Smb2ChannelCapabilities.NETWORK_INTERFACE_INFO_SIZE).order(ByteOrder.LITTLE_ENDIAN);

        // Next field (4 bytes) - offset to next entry
        int next = bb.getInt();

        // InterfaceIndex (4 bytes)
        int ifIndex = bb.getInt();

        // Capability (4 bytes)
        int capability = bb.getInt();

    assertThrows(
        ConcurrentModificationException.class,
        () -> {
          Iterator<Entry<K, V>> iterator = getMap().entrySet().iterator();
          getMap().clear();
          iterator.next();
        });
  }

  @MapFeature.Require({FAILS_FAST_ON_CONCURRENT_MODIFICATION, SUPPORTS_REMOVE})
  @CollectionSize.Require(SEVERAL)
  public void testClearConcurrentWithKeySetIteration() {
    assertThrows(

    assertThrows(NoSuchElementException.class, empty::next);
    assertThrows(UnsupportedOperationException.class, empty::remove);
  }

  public void testBroken() {
    Iterator<Object> broken = new BrokenAbstractSequentialIterator();
    assertTrue(broken.hasNext());
    // We can't retrieve even the known first element:
    assertThrows(SomeUncheckedException.class, broken::next);

/// tip

The next sections are **not necessarily "advanced"**.

And it's possible that for your use case, the solution is in one of them.

///

## Read the Tutorial first { #read-the-tutorial-first }

The next sections assume you already read the main [Tutorial - User Guide: Security](../../tutorial/security/index.md).

        Iterator<Dependency> sourceIterator = source.getDependencies().iterator();
        builder.dependencies(target.getDependencies().stream()
                .map(d -> mergeDependency(d, sourceIterator.next(), sourceDominant, context))
                .collect(Collectors.toList()));
    }

    @Override
    protected void mergeDependency_Exclusions(
            Dependency.Builder builder,
            Dependency target,

            @Override
            protected @Nullable N computeNext() {
              while (nodeConnections.hasNext()) {
                NodeConnection<N> nodeConnection = nodeConnections.next();
                boolean added = seenNodes.add(nodeConnection.node);
                if (added) {
                  return nodeConnection.node;
                }
              }
              return endOfData();

    Iterator<? extends T> it = iterable.iterator();
    if (it.hasNext()) {
      T prev = it.next();
      while (it.hasNext()) {
        T next = it.next();
        if (compare(prev, next) > 0) {
          return false;
        }
        prev = next;
      }
    }
    return true;
  }

  /**

         *
         * @return number of retry attempts
         */
        public int getRetryCount() {
            return retryCount;
        }

        /**
         * Get next retry time
         *
         * @return time of next retry attempt
         */
        public long getNextRetryTime() {
            return nextRetryTime;
        }

        /**
         * Check if recovery should be attempted