* concat(new char[] {a, b}, new char[] {}, new char[] {c}} returns the array {@code {a, b, c}}.
   *
   * @param arrays zero or more {@code char} arrays
   * @return a single array containing all the values from the source arrays, in order
   */
  public static char[] concat(char[]... arrays) {
    int length = 0;
    for (char[] array : arrays) {
      length += array.length;
    }

    /** WAVE DASH */
    public static final char WAVE_DASH = '\u301C';

    /** FULLWIDTH TILDE */
    public static final char FULLWIDTH_TILDE = '\uFF5E';

    /** DOUBLE VERTICAL LINE */
    public static final char DOUBLE_VERTICAL_LINE = '\u2016';

    /** PARALLEL TO */
    public static final char PARALLEL_TO = '\u2225';

    /** MINUS SIGN */
    public static final char MINUS_SIGN = '\u2212';

    // read char by char
    CharSequenceReader reader = new CharSequenceReader(charSequence);
    for (int i = 0; i < expected.length(); i++) {
      assertEquals(expected.charAt(i), reader.read());
    }
    assertFullyRead(reader);

    // read all to one array
    reader = new CharSequenceReader(charSequence);
    char[] buf = new char[expected.length()];

    @Override
    MessageBuilder append(char c);

    /**
     * Append content to the message buffer.
     *
     * @param value the content to append
     * @param offset the index of the first {@code char} to append
     * @param len the number of {@code char}s to append
     * @return the current builder
     */
    @Nonnull
    default MessageBuilder a(char[] value, int offset, int len) {

        Settings settings = new Settings();
        Mirror mirror = new Mirror();
        mirror.setId("local");
        settings.addMirror(mirror);
        mirror = new Mirror();
        mirror.setId("illegal\\:/chars");
        mirror.setUrl("http://void");
        mirror.setMirrorOf("void");
        settings.addMirror(mirror);

        SimpleProblemCollector problems = new SimpleProblemCollector();

        }

        @Override
        public void print(char c) {
            final PrintStream currentStream = getOutputStreamForCurrentThread();
            synchronized (currentStream) {
                currentStream.print(c);
                currentStream.notifyAll();
            }
        }

        @Override
        public void println(char x) {

/**
 * FlatRepositoryLayout
 */
@Named("flat")
@Singleton
@Deprecated
public class FlatRepositoryLayout implements ArtifactRepositoryLayout {

    private static final char ARTIFACT_SEPARATOR = '-';

    private static final char GROUP_SEPARATOR = '.';

    public String getId() {
        return "flat";
    }

    public String pathOf(Artifact artifact) {

    StringBuilder builder = new StringBuilder("abc");
    List<Character> chars = Lists.charactersOf(builder);
    assertEquals(asList('a', 'b', 'c'), chars);
    builder.append("def");
    assertEquals(asList('a', 'b', 'c', 'd', 'e', 'f'), chars);
    builder.deleteCharAt(5);
    assertEquals(asList('a', 'b', 'c', 'd', 'e'), chars);
  }

  public void testNewArrayListEmpty() {

                new char[] {(char) 2, (char) 3, (char) 4}))
        .isEqualTo(2);
    assertThat(
            Chars.indexOf(
                new char[] {(char) 2, (char) 2, (char) 3, (char) 4, (char) 2, (char) 3, (char) 4},
                new char[] {(char) 2, (char) 3, (char) 4}))
        .isEqualTo(1);
    assertThat(
            Chars.indexOf(

     *
     * <p>It is strongly encouraged to use {@link #add(String, char)} instead and give value a
     * readable name.
     *
     * @since 18.0 (since 11.0 as {@code Objects.ToStringHelper.addValue()}).
     */
    @CanIgnoreReturnValue
    public ToStringHelper addValue(char value) {
      return addUnconditionalHolder(String.valueOf(value));
    }

    /**