* is an immutable <i>supplier</i> of {@code Writer} instances.
 *
 * <p>{@code CharSink} provides two kinds of methods:
 *
 * <ul>
 *   <li><b>Methods that return a writer:</b> These methods should return a <i>new</i>, independent
 *       instance each time they are called. The caller is responsible for ensuring that the
 *       returned writer is closed.

    }

    /**
     * Gets the user identifier from this credential.
     *
     * @return The username from SPNEGO authentication
     */
    @Override
    public String getUserId() {
        return username;
    }

    /**
     * Returns a string representation of this credential.
     *
     * @return A string representation containing the username in braces
     */
    @Override

  static <N, E> UndirectedNetworkConnections<N, E> of() {
    return new UndirectedNetworkConnections<>(HashBiMap.<E, N>create(EXPECTED_DEGREE));
  }

  static <N, E> UndirectedNetworkConnections<N, E> ofImmutable(Map<E, N> incidentEdges) {
    return new UndirectedNetworkConnections<>(ImmutableBiMap.copyOf(incidentEdges));
  }

  @Override
  public Set<N> adjacentNodes() {

            @Override
            public LongAddable get() {
              return new LongAdder();
            }
          };
    } catch (Throwable t) { // we really want to catch *everything*
      supplier =
          new Supplier<LongAddable>() {
            @Override
            public LongAddable get() {
              return new PureJavaLongAddable();
            }
          };
    }
    SUPPLIER = supplier;

  @Override
  public SampleElements<String> samples() {
    return new Strings();
  }

  @Override
  public List<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (String) e;
    }
    return create(array);
  }

  /**

    this.options = ImmutableSet.copyOf(options);
  }

  byte[] getBytes() {
    return bytes.toByteArray();
  }

  @Override
  public boolean wasStreamOpened() {
    return outputStreamOpened;
  }

  @Override
  public boolean wasStreamClosed() {
    return outputStreamClosed;
  }

  @Override
  public OutputStream openStream() throws IOException {

  @Override
  public SampleElements<Character> samples() {
    return new Chars();
  }

  @Override
  public List<Character> create(Object... elements) {
    Character[] array = new Character[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (Character) e;
    }
    return create(array);
  }

  /**

  @Override
  public SampleElements<UnhashableObject> samples() {
    return new Unhashables();
  }

  @Override
  public T create(Object... elements) {
    UnhashableObject[] array = createArray(elements.length);
    int i = 0;
    for (Object e : elements) {
      array[i++] = (UnhashableObject) e;
    }
    return create(array);
  }

  /**

    checkNotNull(callable);
    checkNotNull(executor);
    return submitAsync(
        new AsyncCallable<T>() {
          @Override
          public ListenableFuture<T> call() throws Exception {
            return immediateFuture(callable.call());
          }

          @Override
          public String toString() {
            return callable.toString();
          }
        },
        executor);
  }

    return classInfo(cls, cls.getClassLoader());
  }

  private static ClassInfo classInfo(Class<?> cls, ClassLoader classLoader) {
    String resource = cls.getName().replace('.', '/') + ".class";
    return new ClassInfo(FILE, resource, classLoader);
  }

  private static Manifest manifestClasspath(String classpath) throws IOException {
    return manifest("Class-Path: " + classpath + "\n");
  }