assertEquals(1, buf.get(1));
assertEquals('A', buf.get(2));
buf.sweep();
buf.putPrefixedString("A", 4, encoder);
assertEquals(5, buf.position());
assertEquals(0, buf.get(0));
assertEquals(0, buf.get(1));
assertEquals(0, buf.get(2));
assertEquals(1, buf.get(3));
assertEquals('A', buf.get(4));