The J-17 appears to be a knock off of the F-16.
Not a knockoff; it has legitimate American origins.
http://www.globalsecurity.org/military/world/china/j-7p.htm
And a really poor one at that, combined with an F-20 Tiger Shark. Makes for one ugly aircraft.
The J-20 appears to be 2x the size of the F-22 and F-35.
China doing what China does best, copying the US.