Java code!

There is a kind of puzzle formatted as a 9 by 9 grid of cells grouped into nine 3 by 3 boxes. To solve this puzzle the numbers 1 through 9 must appear once, and only once, in each row, column, and 3 by 3 box. The puzzle begins with several cells filled in. Use the generalized backtracking algorithm to solve this kind of puzzle.

the method to use is recursive method not backtraking as the question asked

the code need to tested and also complie otherwise , it will throgth errors and also a copy to code with snap to see the result ohterwise , it is time consuming and code falier