* the call to {@code contains(null)} is permitted to throw a {@code NullPointerException}.
   *
   * @param message message to use upon assertion failure
   */
  protected void expectNullKeyMissingWhenNullKeysUnsupported(String message) {
    try {
      assertFalse(message, getMap().containsKey(null));
    } catch (NullPointerException tolerated) {
      // Tolerated
    }
  }

  /**

          return false;
        }
        int result = 0;
        for (int i = 0; i < a.length; i++) {
          result |= a[i] ^ b[i];
        }
        return (result == 0);
      }
    },
    MESSAGE_DIGEST_IS_EQUAL {
      @Override
      boolean doEquals(byte[] a, byte[] b) {
        return MessageDigest.isEqual(a, b);
      }
    },
    ARRAYS_EQUALS {
      @Override

          return false;
        }
        int result = 0;
        for (int i = 0; i < a.length; i++) {
          result |= a[i] ^ b[i];
        }
        return (result == 0);
      }
    },
    MESSAGE_DIGEST_IS_EQUAL {
      @Override
      boolean doEquals(byte[] a, byte[] b) {
        return MessageDigest.isEqual(a, b);
      }
    },
    ARRAYS_EQUALS {
      @Override

  /** Constructs a {@code VerifyException} with no message. */
  public VerifyException() {}

  /** Constructs a {@code VerifyException} with the message {@code message}. */
  public VerifyException(@CheckForNull String message) {
    super(message);
  }

  /**
   * Constructs a {@code VerifyException} with the cause {@code cause} and a message that is {@code

  /** Constructs a {@code VerifyException} with no message. */
  public VerifyException() {}

  /** Constructs a {@code VerifyException} with the message {@code message}. */
  public VerifyException(@CheckForNull String message) {
    super(message);
  }

  /**
   * Constructs a {@code VerifyException} with the cause {@code cause} and a message that is {@code

   */
  @Deprecated
  protected ExecutionError(@CheckForNull String message) {
    super(message);
  }

  /**
   * Creates a new instance with the given detail message and cause. Prefer to provide a
   * non-nullable {@code cause}, as many users expect to find one.
   */
  public ExecutionError(@CheckForNull String message, @CheckForNull Error cause) {
    super(message, cause);
  }

  /**

      throw new IllegalArgumentException(name + " must be positive but was: " + value);
    }
  }

  /**
   * Precondition tester for {@code Iterator.remove()} that throws an exception with a consistent
   * error message.
   */
  static void checkRemove(boolean canRemove) {
    checkState(canRemove, "no calls to next() since the last call to remove()");
  }

      throw new IllegalArgumentException(name + " must be positive but was: " + value);
    }
  }

  /**
   * Precondition tester for {@code Iterator.remove()} that throws an exception with a consistent
   * error message.
   */
  static void checkRemove(boolean canRemove) {
    checkState(canRemove, "no calls to next() since the last call to remove()");
  }

@GwtCompatible
public class ConflictingRequirementsException extends Exception {
  private Set<Feature<?>> conflicts;
  private Object source;

  public ConflictingRequirementsException(
      String message, Set<Feature<?>> conflicts, Object source) {
    super(message);
    this.conflicts = conflicts;
    this.source = source;
  }

  public Set<Feature<?>> getConflicts() {
    return conflicts;
  }

  public Object getSource() {

    assertArrayEquals("toArray(largeEnough) order should match list", createOrderedArray(), actual);
  }

  private static void assertArrayEquals(String message, Object[] expected, Object[] actual) {
    assertEquals(message, Arrays.asList(expected), Arrays.asList(actual));
  }