try {
        output.writeChars(s);
      } catch (IOException impossible) {
        throw new AssertionError(impossible);
      }
    }

    @Override
    public void writeDouble(double v) {
      try {
        output.writeDouble(v);
      } catch (IOException impossible) {
        throw new AssertionError(impossible);
      }
    }

    @Override
    public void writeFloat(float v) {
      try {

    out.writeShort((short) 50000);
    out.writeInt(0xCAFEBABE);
    out.writeLong(0xDEADBEEFCAFEBABEL);
    out.writeUTF("Herby Derby");
    out.writeFloat(Float.intBitsToFloat(0xCAFEBABE));
    out.writeDouble(Double.longBitsToDouble(0xDEADBEEFCAFEBABEL));
  }

  public void testReadFully() throws IOException {
    DataInput in = new LittleEndianDataInputStream(new ByteArrayInputStream(data));

    out.writeShort((short) 50000);
    out.writeInt(0xCAFEBABE);
    out.writeLong(0xDEADBEEFCAFEBABEL);
    out.writeUTF("Herby Derby");
    out.writeFloat(Float.intBitsToFloat(0xCAFEBABE));
    out.writeDouble(Double.longBitsToDouble(0xDEADBEEFCAFEBABEL));

    byte[] data = baos.toByteArray();

    /* Setup input streams */
    DataInput in = new DataInputStream(new ByteArrayInputStream(data));

    out.writeShort((short) 50000);
    out.writeInt(0xCAFEBABE);
    out.writeLong(0xDEADBEEFCAFEBABEL);
    out.writeUTF("Herby Derby");
    out.writeFloat(Float.intBitsToFloat(0xCAFEBABE));
    out.writeDouble(Double.longBitsToDouble(0xDEADBEEFCAFEBABEL));

    byte[] data = baos.toByteArray();

    /* Setup input streams */
    DataInput in = new DataInputStream(new ByteArrayInputStream(data));

   *
   * @serialData The current value is emitted (a {@code double}).
   */
  private void writeObject(ObjectOutputStream s) throws IOException {
    s.defaultWriteObject();

    s.writeDouble(get());
  }

  /** Reconstitutes the instance from a stream (that is, deserializes it). */
  private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
    s.defaultReadObject();

    // Write out array length
    int length = length();
    s.writeInt(length);

    // Write out all elements in the proper order.
    for (int i = 0; i < length; i++) {
      s.writeDouble(get(i));
    }
  }

  /** Reconstitutes the instance from a stream (that is, deserializes it). */
  private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {

    assertThat(out.toByteArray()).isEqualTo(new byte[] {0x12, 0x34});
  }

  public void testNewDataOutput_writeDouble() {
    ByteArrayDataOutput out = ByteStreams.newDataOutput();
    out.writeDouble(Double.longBitsToDouble(0x1234567876543210L));
    assertThat(out.toByteArray()).isEqualTo(bytes);
  }

  public void testNewDataOutput_writeFloat() {
    ByteArrayDataOutput out = ByteStreams.newDataOutput();

    assertThat(out.toByteArray()).isEqualTo(new byte[] {0x12, 0x34});
  }

  public void testNewDataOutput_writeDouble() {
    ByteArrayDataOutput out = ByteStreams.newDataOutput();
    out.writeDouble(Double.longBitsToDouble(0x1234567876543210L));
    assertThat(out.toByteArray()).isEqualTo(bytes);
  }

  public void testNewDataOutput_writeFloat() {
    ByteArrayDataOutput out = ByteStreams.newDataOutput();