public static ByteBuf copyDouble(double value) {
        ByteBuf buf = buffer(8);
        buf.writeDouble(value);
        return buf;
    }
@Test
    public void testWrapSingleDouble() {
        ByteBuf buffer = copyDouble(42);
        assertEquals(8, buffer.capacity());
        assertEquals(42, buffer.readDouble(), 0.01);
        assertFalse(buffer.isReadable());
        buffer.release();
    }