app/src/main/java/sudoku/Solver.java

@@ -12,11 +12,7 @@ public class Solver implements SudokuSolver {
 
     /** {@inheritDoc} */
     @Override
-    public void setBoard(int[][] board) throws IllegalArgumentException, NullPointerException {
+    public void setBoard(int[][] board) {
-        if (board == null)
-            throw new NullPointerException("Board cannot be null");
-        if (board.length != 9 || board[0].length != 9)
-            throw new IllegalArgumentException("Board must be 9x9");
         this.board = board;
     }
 
@@ -32,7 +28,7 @@ public class Solver implements SudokuSolver {
         board = new int[9][9];
     }
 
-    /* {@inheritDoc} */
+    /*{@inheritDoc} */
     @Override
     public boolean solve() {
         return solve(0, 0);
@@ -111,7 +107,7 @@ public class Solver implements SudokuSolver {
         }
 
         // Recursively call randomizeBoard() until we get a solvable board
-        // This is expensive, and there should be a better way to do this
+        // This is expensive, and there should be some voodoo magic that computes this in n^2 time
         if (!isSolvable()) {
             randomizeBoard(difficulty);
         }

app/src/main/java/sudoku/SudokuSolver.java

@@ -1,6 +1,5 @@
 package sudoku;
 
-/** SudokuSolver is an interface for implementing Sudoku solvers */
 public interface SudokuSolver {
     /**
      * Set sudoku board, numbers 1-9 are fixed values, 0 is unsolved.
@@ -8,12 +7,10 @@ public interface SudokuSolver {
      * @param board a board to copy values from
      * @throws IllegalArgumentException if board is invalid, e.g. not 9x9
      */
-    void setBoard(int[][] board) throws IllegalArgumentException, NullPointerException;
+    void setBoard(int[][] board) throws IllegalArgumentException;
 
     /**
      * Get a copy of the sudoku board
-     * 
-     * @return a <b>copy</b> of the sudoku board
      */
     int[][] getBoard();
 
@@ -27,9 +24,9 @@ public interface SudokuSolver {
     /**
      * Check if digit is legal on the current board
      * 
-     * @param row row
+     * @param row
-     * @param col column
+     * @param col
-     * @param nbr number to check
+     * @param nbr
      * @return true if legal
      */
     boolean isLegal(int row, int col, int nbr);
@@ -37,8 +34,8 @@ public interface SudokuSolver {
     /**
      * Get number on board
      * 
-     * @param row row
+     * @param row
-     * @param col column
+     * @param col
      * @return number on board
      */
     int get(int row, int col);
@@ -46,9 +43,9 @@ public interface SudokuSolver {
     /**
      * Set number on board, numbers 1-9 are fixed values, 0 is unsolved.
      * 
-     * @param row row
+     * @param row
-     * @param col column
+     * @param col
-     * @param nbr number to set
+     * @param nbr
      */
     void set(int row, int col, int nbr);
 

app/src/test/java/sudoku/SolverTest.java

@@ -106,11 +106,4 @@ class SolverTest {
         solver.set(7, 1, 8);
         assertFalse(solver.solve());
     }
-
-    @Test
-    void setBoardInvalidInputThrowsTest() {
-        Solver solver = new Solver();
-        assertThrows(NullPointerException.class, () -> solver.setBoard(null));
-        assertThrows(IllegalArgumentException.class, () -> solver.setBoard(new int[8][8]));
-    }
 }