* @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class CharStreams {

  // 2K chars (4K bytes)
  private static final int DEFAULT_BUF_SIZE = 0x800;

  /** Creates a new {@code CharBuffer} for buffering reads or writes. */
  static CharBuffer createBuffer() {
    return CharBuffer.allocate(DEFAULT_BUF_SIZE);
  }

  private CharStreams() {}

  /**

    Reader empty = new StringReader("");
    assertEquals(0, CharStreams.exhaust(empty));
    assertEquals(-1, empty.read());
  }

  public void testExhaust_readable() throws IOException {
    CharBuffer buf = CharBuffer.wrap(ASCII);
    assertEquals(ASCII.length(), CharStreams.exhaust(buf));
    assertEquals(0, buf.remaining());
    assertEquals(0, CharStreams.exhaust(buf));

    Reader empty = new StringReader("");
    assertEquals(0, CharStreams.exhaust(empty));
    assertEquals(-1, empty.read());
  }

  public void testExhaust_readable() throws IOException {
    CharBuffer buf = CharBuffer.wrap(ASCII);
    assertEquals(ASCII.length(), CharStreams.exhaust(buf));
    assertEquals(0, buf.remaining());
    assertEquals(0, CharStreams.exhaust(buf));