```
public class Sudoku
extends Object
```
Class representing Sudoku riddle.

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`Sudoku.DigitImmutableException`	Custom exception thrown when trying to modify hard-coded sudoku field.
`static class`	`Sudoku.DigitOutOfRangeException`	Custom exception thrown when a board digit is negative or greater than sudoku rank (0 indicates an empty field).
`static class`	`Sudoku.IncorrectBoardSizeException`	Custom exception thrown when trying to initialize board with incorrect size.

Field Summary

Fields
Modifier and Type	Field	Description
`private int[][]`	`_board`	Current values of board fields
`private boolean[][]`	`_mask`	Array of flags indicating hard-coded board fields.
`private int`	`_rank`	Size of a single (small) sudoku square (aka. block)
`private int`	`_size`	Board size

Constructor Summary

Constructors
Constructor Description

Sudoku(int rank)

Sudoku(Sudoku sudoku)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`equals(Object o)`
`int[][]`	`getBoard()`
`int`	`getDigit(int x, int y)`
`int`	`getEmptyFieldsCount()`
`boolean`	`getMask(int x, int y)`
`int`	`getPlayerCount()`
`int`	`getRank()`
`int`	`getSize()`
`int`	`getTableCount()`
`void`	`insertDigit(int x, int y, int digit)`
`void`	`printNatural()`	Prints the board of the Sudoku in natural, human-friendly style.
`void`	`reset()`	Reset board to default state.
`void`	`setBoard(int[][] board)`	Set board default state.

Methods inherited from class java.lang.Object
clone, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail
- _rank
```
private final int _rank
```
  Size of a single (small) sudoku square (aka. block)
- _size
```
private final int _size
```
  Board size
- _board
```
private int[][] _board
```
  Current values of board fields
- _mask
```
private boolean[][] _mask
```
  Array of flags indicating hard-coded board fields. If true, field cannot be modified.

Constructor Detail

Sudoku
```
public Sudoku(int rank)
```

Sudoku
```
public Sudoku(Sudoku sudoku)
```

Method Detail

getBoard
```
public int[][] getBoard()
```

setBoard
```
public void setBoard(int[][] board)
```
Set board default state.

Parameters:

board - 2d array of sudoku digits (0 means that the field is empty)

reset
```
public void reset()
```
Reset board to default state. Sets all unmasked board fields to zero (empty).

insertDigit

public void insertDigit(int x,
                        int y,
                        int digit)

getDigit

public int getDigit(int x,
                    int y)

getMask

public boolean getMask(int x,
                       int y)

getSize
```
public int getSize()
```

getRank
```
public int getRank()
```

getPlayerCount
```
public int getPlayerCount()
```

getTableCount
```
public int getTableCount()
```

getEmptyFieldsCount
```
public int getEmptyFieldsCount()
```

printNatural
```
public void printNatural()
```
Prints the board of the Sudoku in natural, human-friendly style.

equals
```
public boolean equals(Object o)
```
Overrides:

equals in class Object

Constructors
Constructor	Description
`Sudoku(int rank)`
`Sudoku(Sudoku sudoku)`

Class Sudoku

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

_rank

_size

_board

_mask

Constructor Detail

Sudoku

Sudoku

Method Detail

getBoard

setBoard

reset

insertDigit

getDigit

getMask

getSize

getRank

getPlayerCount

getTableCount

getEmptyFieldsCount

printNatural

equals