Not just Jupiter - any "outer planet" doesn't have a solid surface. The planets (at least in our solar system) are divided between inner planets (Mercury, Venus, Earth and Mars) and outer planets (Jupiter, Saturn, Uranus and Neptune). read more
Jupiter has clearly passed the three tests to qualify as a planet. And a simple food for thought, it is speculated that there is a surface in Gas giants too, although the entire planet is mostly composed of gases. read more