### Question:
DataStream { @SuppressWarnings("SimplifiableIfStatement") public boolean write(@Nullable final byte[] data) { if (data == null) return false; return write(data, 0, data.length); } DataStream(); @SuppressWarnings("SimplifiableIfStatement") boolean write(@Nullable final byte[] data); boolean write(@Nullable final byte[] data,
						 @IntRange(from = 0) final int offset, @IntRange(from = 0) final int length); boolean write(@Nullable final Data data); @IntRange(from = 0) int size(); @NonNull byte[] toByteArray(); @NonNull Data toData();  }### Answer:
@Test public void write() { final DataStream stream = new DataStream(); stream.write(new byte[] { 0, 1, 2, 3}); stream.write(new byte[] { 4, 5, 6}); assertArrayEquals(new byte[] { 0, 1, 2, 3, 4, 5, 6}, stream.toByteArray()); }