Develop Reference

How to pause graphics of JPanel using Swing Timer?

I am building a Sudoku Solver visualizer that will solve the sudoku board and show the computer's steps as it tries each number in the available slots. I have been using the JFrame/JPanel framework to visualize this but have had problems updating the graphics to show the computer solving it and pausing the graphics in between each new attempt at each slot.
The solver works perfectly and correctly solves the board but I can only see the unsolved board and the solved board when I click the enter button.
Here is my class with the main method:
public class sudokuSolverVisualizer {
public static void main(String[] args) {
new GameFrame();
}
}
Here is the Game Frame class:
import javax.swing.*;
public class GameFrame extends JFrame {
GameFrame(){
this.add(new GamePanel());
this.setTitle("Sudoku Solver");
this.setResizable(false);
this.pack();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setLocationRelativeTo(null);
this.setVisible(true);
}
}
And here is my JPanel class that solves the sudoku board and updates the graphics:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.Line2D;
public class GamePanel extends JPanel implements ActionListener {
//region Variable Declaration
private static final int SIZE = 9;
static final int SCREEN_WIDTH = 270;
static final int SCREEN_HEIGHT = 270;
static final int UNIT_SIZE = SCREEN_WIDTH/SIZE;
static final int GAME_DELAY = 25;
static final int[][] board = {
{7, 0, 2, 0, 5, 0, 6, 0, 0},
{0, 0, 0, 0, 0, 3, 0, 0, 0},
{1, 0, 0, 0, 0, 9, 5, 0, 0},
{8, 0, 0, 0, 0, 0, 0, 9, 0},
{0, 4, 3, 0, 0, 0, 7, 5, 0},
{0, 9, 0, 0, 0, 0, 0, 0, 8},
{0, 0, 9, 7, 0, 0, 0, 0, 5},
{0, 0, 0, 2, 0, 0, 0, 0, 0},
{0, 0, 7, 0, 4, 0, 2, 0, 3}
};
static boolean solving = false;
static boolean solved = false;
static Timer timer;
//endregion
GamePanel(){
this.setPreferredSize(new Dimension(SCREEN_WIDTH, SCREEN_HEIGHT));
this.setBackground(Color.lightGray);
this.setFocusable(true);
this.addKeyListener(new MyKeyAdapter());
startGame();
}
public void paintComponent(Graphics g){
super.paintComponent(g);
draw(g);
}
public void startGame(){
timer = new Timer(GAME_DELAY, this);
timer.start();
}
private static void draw(Graphics g) {
if (solving){
solveBoard(board, g);
}
Graphics2D g2 = (Graphics2D) g;
for (int row = 0; row < SIZE; row++){
if (row % 3 == 0 && row != 0){
g2.setStroke(new BasicStroke(5));
} else {
g2.setStroke(new BasicStroke(1));
}
g2.draw(new Line2D.Float(0, row * UNIT_SIZE, SCREEN_WIDTH, row * UNIT_SIZE));
for (int column = 0; column < SIZE; column++){
if (column % 3 == 0 && column != 0){
g2.setStroke(new BasicStroke(5));
} else {
g2.setStroke(new BasicStroke(1));
}
g2.draw(new Line2D.Float(column * UNIT_SIZE, 0, column * UNIT_SIZE, SCREEN_HEIGHT));
if (solved){
g.setColor(Color.green);
}
g2.drawString(String.valueOf(board[row][column]), column * UNIT_SIZE + 12, row * UNIT_SIZE + 22);
g.setColor(Color.black);
}
}
}
private static boolean isInRow(int[][] board, int num, int row){
for (int i = 0; i < SIZE; i++){
if (board[row][i] == num){
return true;
}
}
return false;
}
private static boolean isInColumn(int[][] board, int num, int column){
for (int i = 0; i < SIZE; i++){
if (board[i][column] == num){
return true;
}
}
return false;
}
private static boolean isInBox(int[][] board, int num, int row, int column){
int rowStart = row - row % 3;
int columnStart = column - column % 3;
for (int i = rowStart; i < rowStart + 3; i++){
for (int j = columnStart; j < columnStart + 3; j++) {
if (board[i][j] == num) {
return true;
}
}
}
return false;
}
private static boolean isValidPlace(int[][] board, int num, int row, int column){
return !isInRow(board, num, row) &&
!isInColumn(board, num, column) &&
!isInBox(board, num, row, column);
}
private static boolean solveBoard(int[][] board, Graphics g){
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.black);
for (int row = 0; row < SIZE; row++) {
for (int column = 0; column < SIZE; column++) {
if (board[row][column] == 0) {
for (int num = 1; num <= SIZE; num++) {
if (isValidPlace(board, num, row, column)) {
board[row][column] = num;
drawElements(g2, row, column, true);
if (solveBoard(board, g)) {
return true;
}
else{
board[row][column] = 0;
drawElements(g2, row, column, false);
}
}
}
return false;
}
}
}
solving = false;
solved = true;
draw(g);
return true;
}
private static void drawElements(Graphics2D g2, int row, int column, boolean correct){
if (correct) {
g2.setColor(Color.green);
} else {
g2.setColor(Color.red);
}
g2.clearRect(column * UNIT_SIZE, row * UNIT_SIZE, UNIT_SIZE, UNIT_SIZE);
g2.drawString(String.valueOf(board[row][column]), column * UNIT_SIZE + 12, row * UNIT_SIZE + 22);
g2.drawRect(column * UNIT_SIZE, row * UNIT_SIZE, UNIT_SIZE, UNIT_SIZE);
g2.setColor(Color.black);
}
private static void printBoard(int[][] board){
for (int row = 0; row < SIZE; row++){
if (row % 3 == 0 && row != 0){
System.out.println("-------------------");
}
for (int column = 0; column < SIZE; column++){
if (column % 3 == 0 && column != 0){
System.out.print("|");
}
System.out.print(board[row][column] + " ");
}
System.out.println();
}
}
#Override
public void actionPerformed(ActionEvent e) {
if (solving) {
repaint();
}
}
public class MyKeyAdapter extends KeyAdapter {
#Override
public void keyPressed(KeyEvent e) {
switch (e.getKeyCode()){
case KeyEvent.VK_ENTER:
solving = true;
break;
}
}
}
}
If you could help me find a way to pause the graphics in between each attempt at each slot or somehow repaint the graphics every time it tries a number, that would be great!

Visualising recursion like this is very hard, because what you need is control over the flow. Rather than the algorithm being allowed to run "freely", you need some way that you can control each iteration.
The first thing I did was adapted a non-recursive solver algorithm from Java | Recursive and non-recursive Sudoku solutions (Starter-friendly)
This allowed to create a step method which would move the solution along by a single (or close enough for the purpose) step.
This means that I can call step from Timer and control when the algorithm updates.
Important
This is NOT a Sudoku solution, this focus on how you might adopt a "recursive" style algorithm so it can be visualised, I take no responsibility for the accuracy of the algorithm 😉
Runnable example
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.time.Duration;
import java.time.Instant;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.Stack;
import java.util.StringJoiner;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Main {
int[][] board = {
{7, 0, 2, 0, 5, 0, 6, 0, 0},
{0, 0, 0, 0, 0, 3, 0, 0, 0},
{1, 0, 0, 0, 0, 9, 5, 0, 0},
{8, 0, 0, 0, 0, 0, 0, 9, 0},
{0, 4, 3, 0, 0, 0, 7, 5, 0},
{0, 9, 0, 0, 0, 0, 0, 0, 8},
{0, 0, 9, 7, 0, 0, 0, 0, 5},
{0, 0, 0, 2, 0, 0, 0, 0, 0},
{0, 0, 7, 0, 4, 0, 2, 0, 3}
};
public static void main(String[] args) {
new Main();
}
public Main() {
// print(board);
SudokuSolver solver = new SudokuSolver(board);
// System.out.println();
print(solver.solve());
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
SudokuSolver solver = new SudokuSolver(board);
JFrame frame = new JFrame("Test");
frame.add(new MainPane(solver));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public void print(int[][] board) {
for (int[] row : board) {
StringJoiner joiner = new StringJoiner(" ", "", "\n");
for (int cell : row) {
joiner.add(String.format("%d", cell));
}
System.out.print(joiner.toString());
}
}
public class MainPane extends JPanel {
private SolverPane solverPane;
public MainPane(SudokuSolver solver) {
setLayout(new BorderLayout());
solverPane = new SolverPane(solver);
add(solverPane);
JButton startButton = new JButton("Go");
startButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
startButton.setEnabled(false);
solverPane.start(new SolverPane.Observer() {
#Override
public void didCompleteSolution() {
startButton.setEnabled(true);
}
});
}
});
add(startButton, BorderLayout.SOUTH);
}
}
public class SolverPane extends JPanel {
public interface Observer {
public void didCompleteSolution();
}
private SudokuSolver solver;
private Observer observer;
private Dimension preferredSize;
private int gap = 4;
public SolverPane(SudokuSolver solver) {
this.solver = solver;
solver.prepareSolution();
setFont(new Font("Monospaced", Font.PLAIN, 20));
}
#Override
public Dimension getPreferredSize() {
if (preferredSize == null) {
FontMetrics fm = getFontMetrics(getFont());
preferredSize = new Dimension(10 + ((fm.stringWidth("0") + gap) * 9), 10 + (fm.getHeight() * 9));
}
return preferredSize;
}
public void start(Observer observer) {
this.observer = observer;
solver.prepareSolution();
Instant startedAt = Instant.now();
Timer timer = new Timer(5, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (solver.step()) {
observer.didCompleteSolution();
((Timer) e.getSource()).stop();
Duration duration = Duration.between(Instant.now(), startedAt);
System.out.println(duration);
}
repaint();
}
});
timer.start();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
FontMetrics fm = g2d.getFontMetrics();
int gap = 4;
int cellWidth = fm.stringWidth("0") + 4;
int xPos = (getWidth() - (cellWidth * 9)) / 2;
int yPos = (getHeight() - (cellWidth * 9)) / 2;
g2d.translate(xPos, yPos);
Stack<SudokuSolver.Cell> solved = solver.getSolved();
if (solved != null) {
for (SudokuSolver.Cell cell : solver.getSolved()) {
int x = cell.getCol() * cellWidth;
int y = ((cell.getRow() - 1) * fm.getHeight());
g2d.drawString(Integer.toString(cell.getValue()), x, y);
}
}
g2d.dispose();
}
}
class SudokuSolver {
// Adapted from https://leetcode.com/problems/sudoku-solver/discuss/1392747/java-recursive-and-non-recursive-sodoku-solutions-starter-friendly
private int[][] board;
private LinkedList<Cell> unsolved;
private Stack<Cell> solved;
public SudokuSolver(int[][] originalBoard) {
this.board = originalBoard;
}
public LinkedList<Cell> getUnsolved() {
return unsolved;
}
public Stack<Cell> getSolved() {
return solved;
}
protected void prepareSolution() {
// all we need are just 1 stack, and 1 queue.
unsolved = new LinkedList<>(); // queue: all unconfirmed cells
solved = new Stack<>(); // stack: all cells which are confirmed temporarily
// init candidates
for (int i = 0; i < 9; i++) {
for (int j = 0; j < 9; j++) {
if (board[i][j] == 0) {
Cell cell = new Cell(i, j, board);
unsolved.addLast(cell);
} else {
Cell cell = new Cell(i, j);
cell.value = board[i][j];
solved.add(cell);
}
}
}
}
public boolean step() {
if (unsolved == null || solved == null) {
prepareSolution();
}
if (unsolved.peekFirst() == null) {
return true;
}
Cell curr = unsolved.removeFirst();
if (curr.isValidCandid()) {
solved.push(curr); // *
unsolved = excludeCandid(curr, unsolved);
} else { // MARK-s4
unsolved.addFirst(curr); // *
Cell prev = solved.pop(); // *
unsolved = revertCandid(prev, unsolved);
curr.resetCandid(); // restart selection
prev.nextCandid();
unsolved.addFirst(prev); // *
}
return unsolved.peekFirst() == null;
}
public int[][] solve() {
prepareSolution();
// try different combinations until all unsolved cells gone
Cell curr;
while (unsolved.peekFirst() != null) {
curr = unsolved.removeFirst();
if (curr.isValidCandid()) {
solved.push(curr); // *
unsolved = excludeCandid(curr, unsolved);
} else { // MARK-s4
unsolved.addFirst(curr); // *
Cell prev = solved.pop(); // *
unsolved = revertCandid(prev, unsolved);
curr.resetCandid(); // restart selection
prev.nextCandid();
unsolved.addFirst(prev); // *
}
}
int[][] solution = new int[board.length][board.length];
for (int row = 0; row < board.length; row++) {
for (int col = 0; col < board[row].length; col++) {
solution[row][col] = board[row][col];
}
}
// solutions back
while (!solved.empty()) {
confirm(solved.pop(), solution);
}
return solution;
}
void confirm(Cell solution, int[][] problem) {
problem[solution.row][solution.col] = solution.value;
}
// once some candidates are taken, we need to exclude them in related cells
LinkedList<Cell> excludeCandid(Cell target, LinkedList<Cell> before) {
LinkedList<Cell> after = new LinkedList<Cell>();
Cell curr;
while ((curr = before.peekFirst()) != null) {
before.removeFirst();
curr.excludeCandidate(target); // exclude the target candidate
// OPTIONAL, but win more about 70% time!
if (curr.isValidCandid()) // if there is conflict, handle it first
{
after.addLast(curr);
} else {
after.addFirst(curr);
}
}
return after;
}
// once the previous candidates were incorrectly taken, we need to revert/recover them in related cells
LinkedList<Cell> revertCandid(Cell target, LinkedList<Cell> before) {
LinkedList<Cell> after = new LinkedList<Cell>();
Cell curr = null;
while ((curr = before.peekFirst()) != null) {
before.removeFirst();
curr.enableCandidate(target);
after.addLast(curr);
}
return after;
}
// >> SOLUTION
// << STRUCT
public class Cell {
/**
*
* To solve sudoku, we can use one stack to save all temporarily
* confirmed cells, and one queue to save all unconfirmed ones, then
* repeatedly dequeue elements from queue and push them into the
* stack, analysing them at the same time, until queue is empty,
* then Sudoku is solved. If stack encounter EmptyStackException at
* some point of time, this method then is not capable to solve the
* given Sudoku. Note, analysing cells is simple and
* straightforward, just the "pointer" stuff, and the detail is
* shown below.
*
*
* ################################## ## "1 stack and 1 queue" model
* : ##################################
*
* ........................................................................
* .----------- (2,5) (2,4) (2,6) (2,0) .... |
* ........................................................................
* | (unsolved Queue/List) | | \/ | | | | | (2,3) | | .... | | ....
* | | .... | ---------- (solved Stack)
*
*
*
* ################################## ## "candidate pointer" model :
* ( cell(2,0) at any possible point of time )
* ##################################
*
* Characters: 1 2 3 4 5 6 7 8 9
*
* candidates: [-999999, 0 , 33 , -1 , 78 , 0 , 0 , -1 , 0 , -1] ^
* [Stage 1] ... 21 ^ [Stage 2] ... 21 23 22 25 ^(>9) [Stage 3]
*
* Explanations: [Stage 1] candidate pointer(cPtr), when at very
* beginning, and there are 3 possible values that can be chosen;
* [Stage 2] after '1' is selected by 21st cell, i.e. problem[2][2],
* cPtr moves to 5th; [Stage 3] at this point, the '1' was taken by
* 21st cell, '5' was by 23rd, '6' was by 22nd, '8' was by 25th,
* result in cPtr overflow, which means some of previous candidates
* were taken incorrectly, and getting back and retrying is needed.
* [Stage 4] details is shown in some place of codes, marked as
* "MARK-s4"
*
*
*
*/
private int row;
private int col;
private int[] candidates; // -1: confirmed 0: possible >0: be selected by others
private int value = -1; // [1,9] or 10,11,...
public Cell(int i, int j) {
row = i;
col = j;
candidates = new int[10];
candidates[0] = -999999;
}
public Cell(int i, int j, int[][] datasource) {
this(i, j);
initCandidates(datasource);
}
public int getRow() {
return row;
}
public int getCol() {
return col;
}
public int getValue() {
return value;
}
protected void initCandidates(int[][] datasource) {
// same row
for (int i = 0; i < 9; i++) {
if (datasource[row][i] != 0) {
candidates[datasource[row][i]] = -1;
}
}
// same col
for (int i = 0; i < 9; i++) {
if (datasource[i][col] != 0) {
candidates[datasource[i][col]] = -1;
}
}
// same 9-cell
int start_i = row / 3 * 3;
int start_j = col / 3 * 3;
for (int i = start_i; i < start_i + 3; i++) {
for (int j = start_j; j < start_j + 3; j++) {
if (datasource[i][j] != 0) {
candidates[datasource[i][j]] = -1;
}
}
}
// init candid ptr
resetCandid();
}
protected int getCurrCandid() { // [1-9] or -1
if (isValidCandid()) {
return value;
}
return -1;
}
private void resetCandid() {
// to left most 0
int i = 1;
for (; i < 10; i++) {
if (candidates[i] == 0) {
break;
}
}
value = i; // 1..9 or 10
}
private void nextCandid() {
int i = value + 1;
while (i < 10 && candidates[i] != 0) {
i++;
}
value = i; // 1..9 or 10,11,...
}
private void excludeCandidate(Cell by) {
int their = by.getCurrCandid();
if (candidates[their] == 0) {
int theirIdx = by.row * 9 + by.col + 1;
// same row
if (by.row == row) {
candidates[their] = theirIdx;
}
// same col
if (by.col == col) {
candidates[their] = theirIdx;
}
// same cell
if (by.row / 3 * 3 == row / 3 * 3 && by.col / 3 * 3 == col / 3 * 3) {
candidates[their] = theirIdx;
}
}
if (!isValidCandid()) {
nextCandid();
}
}
private void enableCandidate(Cell by) {
int their = by.getCurrCandid(); // must exist
int theirIdx = by.row * 9 + by.col + 1;
if (candidates[their] > 0 && candidates[their] == theirIdx) { // result from their
candidates[their] = 0; // >0 -> 0
if (value >= their) {
resetCandid(); // *
}
}
}
private int numOfCandidate() {
int num = 0;
for (int i = 1; i < 10; i++) {
if (candidates[i] == 0) {
num++;
}
}
return num;
}
private boolean isValidCandid() {
if (value < 1 || value > 9) {
return false;
}
return candidates[value] == 0;
}
public String toString() {
return String.format("%d,%d cptr:%d(%b) (%d)candids:%s\n", row, col, value, isValidCandid(), numOfCandidate(), Arrays.toString(candidates));
}
}
// >> STRUCT
}
}

Rotating game in JPanel

I created a very simple shooting game utilizing JPanel as shown in the code below. I also wanted to experiment with rotating the game and trying it out. I have one issue, where the game I was able to successfully rotate the game but the dimension seems to cut out, and I have to set each position of the enemy and myself to the rotated position.
I was wondering if there was a way to rotate the result as a whole, instead of simply rotating the shape so that the position of the ship and the missiles would also rotate all at once.
Edited code: added three lives to the player and tried implementing heart image with BufferedImage.
public class game extends JFrame{
public game(){
}
public static void main(String[] args){
new game();
}
public class MyJPanel extends JPanel implements ActionListener, MouseListener,
MouseMotionListener,KeyListener
{
//variables for player
int my_x;
int player_width,player_height;
private int lives = 3;
int heart_width, heart_height;
//variables for player's missiles
int my_missile_x, my_missile_y;
int missile_flag;
public static final int MY_Y = 600;
//variables for enemies' missiles
int e_missile_flag[];
int e_missile_x[];
int e_missile_y[];
int e_missile_move[];
Image image,image2;
Timer timer;
private BufferedImage heart;
public MyJPanel(){
missile_flag = 0;
/*** initialize enemies' info ***/
ImageIcon icon2 = new ImageIcon("enemy.jpg");
image2 = icon2.getImage();
enemy_width = image2.getWidth(this);
enemy_height = image2.getHeight(this);
try {
heart = ImageIO.read(getClass().getResource("heart.jpg"));
}catch(IOException e) {
}
heart_width = heart.getWidth(this);
heart_height = heart.getHeight(this);
n = 14; //number of enemies
enemy_x = new int[n];
enemy_y = new int[n];
enemy_move = new int[n];
enemy_alive = new int[n];
int distance = 40;
e_missile_flag = new int[n];
e_missile_x = new int[n];
e_missile_y = new int[n];
e_missile_move = new int[n];
// place enemies in 7x2
for (int i = 0; i < 7; i++) {
enemy_x[i] = (enemy_width + distance) * i + 50;
enemy_y[i] = 50;
}
for (int i = 7; i < n; i++) {
enemy_x[i] = (enemy_width + distance) * (i - 5) + 50;
enemy_y[i] = 100;
}
for (int i = 0; i < n; i++) {
enemy_alive[i] = 1; //all alive
enemy_move[i] = -10; //moves to left
}
for (int i = 0; i < n; i++) {
e_missile_flag[i] = 0;
e_missile_x[i] = 0;
e_missile_y[i] = 0;
e_missile_move[i] = 7 + n%3;
}
/*** setup system ***/
setBackground(Color.black);
setFocusable(true);
addMouseListener(this);
addMouseMotionListener(this);
addKeyListener(this);
timer = new Timer(50, this);
timer.start();
}
private void updateEnemiesPosition(){
//update enemies' position
Dimension dim = getSize();
for (int i = 0; i < n; i++) {
enemy_x[i] += enemy_move[i];
if ((enemy_x[i] < 0) || (enemy_x[i] > (dim.width - enemy_width))) {
enemy_move[i] = -enemy_move[i];
}
}
}
private void updateMyPosition() {
if(my_x < 0) {
my_x = 800;
}
if(my_x > 800) {
my_x = 0;
}
}
private void activateMyMissile(){
//shoot a missile
if(missile_flag == 0){
my_missile_x = my_x + player_width / 2;
my_missile_y = MY_Y; //MY_Y=400
missile_flag = 1;
}
}
private void updateMyMissile(){
//update missile position if alive
if (missile_flag == 1) {
my_missile_y -= 15;
if (0 > my_missile_y) {
missile_flag = 0;
}
}
}
private void activateEnemiesMissile(){
//activate enemies' missile if enemy is alive and its missile is not alive
for(int i = 0; i < n; i++){
if (enemy_alive[i] == 1 && e_missile_flag[i] == 0) {
e_missile_x[i] = enemy_x[i] + enemy_width/2;
e_missile_y[i] = enemy_y[i];
e_missile_flag[i] = 1;
}
}
}
private void updateEnemiesMissile(){
//update enemies' missile position if alive
Dimension dim = getSize();
for(int i = 0; i < n; i++){
if (e_missile_flag[i] == 1) {
e_missile_y[i] += e_missile_move[i];
if (e_missile_y[i] > dim.height) {
e_missile_flag[i] = 0;
}
}
}
}
private void checkHitToEnemy(){
for(int i = 0; i < n; i++){
if(missile_flag == 1 && enemy_alive[i] == 1){
if(
my_missile_x > enemy_x[i] &&
my_missile_x < (enemy_x[i] + enemy_width) &&
my_missile_y > enemy_y[i] &&
my_missile_y < (enemy_y[i] + enemy_height)
){
//hit
missile_flag = 0;
enemy_alive[i] = 0;
}
}
}
}
private boolean checkClear(){
int cnt = 0;
for(int i = 0; i < n; i++){
if(enemy_alive[i] == 0) cnt++;
}
return (n == cnt);
}
if(lives>0) {
int x = 0;
int y = getHeight()- heart.getHeight();
for(int index = 0; index < lives; index++) {
g.drawImage(heart, x, y, this);
x += heart.getWidth();
}
}
g2d.dispose();
}
public void actionPerformed(ActionEvent e){
if (e.getSource() == timer) {
updateEnemiesPosition();
updateMyPosition();
updateMyMissile();
updateEnemiesMissile();
activateEnemiesMissile();
if(checkHitToPlayer()){
System.out.println("===== Game Over =====");
System.exit(0);
}
checkHitToEnemy();
if(checkClear()){
System.out.println("===== Game Clear =====");
System.exit(0);
}
repaint();
}
}
public void mouseClicked(MouseEvent me)
{ }
public void mousePressed(MouseEvent me)
{
activateMyMissile();
}
public void mouseReleased(MouseEvent me)
{ }
public void mouseExited(MouseEvent me)
{ }
public void mouseEntered(MouseEvent me)
{ }
public void mouseMoved(MouseEvent me)
{ }
public void mouseDragged(MouseEvent me)
{ }
public void keyReleased(KeyEvent e){
}
public void keyTyped(KeyEvent e){
}
}
}

The original size of the component is going to be less then 800x500 (I say less then, because the actual size will be 800x500 - the frame decorations - this is why you should be setting the size of the window directly).
When you rotate it 90 degrees, it becomes (less then) 500x800. So, no, there's no "easy" way to resolve this, without making the game square.
I added...
g2d.setColor(Color.DARK_GRAY);
g2d.fillRect(0, 0, getWidth(), getHeight());
after the rotation, which highlights the issue.
To do this, you should override getPreferredSize of the JPanel and the call pack on the frame. This will ensure that that game canvas is sized to it's preferred size and the window decorations are then packed around it.
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Lec12 extends JFrame {
public Lec12() {
setTitle("Game Example");
setDefaultCloseOperation(EXIT_ON_CLOSE);
MyJPanel myJPanel = new MyJPanel();
Container c = getContentPane();
c.add(myJPanel);
pack();
setVisible(true);
}
public static void main(String[] args) {
new Lec12();
}
public class MyJPanel extends JPanel implements ActionListener, MouseListener,
MouseMotionListener, KeyListener {
//variables for player
int my_x;
int player_width, player_height;
//variables for enemies
int enemy_width, enemy_height;
int n;
int enemy_x[];
int enemy_y[];
int enemy_move[];
int enemy_alive[];
//variables for player's missiles
int my_missile_x, my_missile_y;
int missile_flag;
public static final int MY_Y = 400;
//variables for enemies' missiles
int e_missile_flag[];
int e_missile_x[];
int e_missile_y[];
int e_missile_move[];
Image image, image2;
Timer timer;
public MyJPanel() {
/**
* * initialize player's info **
*/
my_x = 250;
ImageIcon icon = new ImageIcon("player.jpg");
image = icon.getImage();
player_width = image.getWidth(this);
player_height = image.getHeight(this);
missile_flag = 0;
/**
* * initialize enemies' info **
*/
ImageIcon icon2 = new ImageIcon("enemy.jpg");
image2 = icon2.getImage();
enemy_width = image2.getWidth(this);
enemy_height = image2.getHeight(this);
n = 14; //number of enemies
enemy_x = new int[n];
enemy_y = new int[n];
enemy_move = new int[n];
enemy_alive = new int[n];
int distance = 40;
e_missile_flag = new int[n];
e_missile_x = new int[n];
e_missile_y = new int[n];
e_missile_move = new int[n];
// place enemies in 7x2
for (int i = 0; i < 7; i++) {
enemy_x[i] = (enemy_width + distance) * i + 50;
enemy_y[i] = 50;
}
for (int i = 7; i < n; i++) {
enemy_x[i] = (enemy_width + distance) * (i - 5) + 50;
enemy_y[i] = 100;
}
for (int i = 0; i < n; i++) {
enemy_alive[i] = 1; //all alive
enemy_move[i] = -10; //moves to left
}
for (int i = 0; i < n; i++) {
e_missile_flag[i] = 0;
e_missile_x[i] = 0;
e_missile_y[i] = 0;
e_missile_move[i] = 7 + n % 3;
}
/**
* * setup system **
*/
setBackground(Color.black);
setFocusable(true);
addMouseListener(this);
addMouseMotionListener(this);
addKeyListener(this);
timer = new Timer(50, this);
timer.start();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(800, 800);
}
private void updateEnemiesPosition() {
//update enemies' position
Dimension dim = getSize();
for (int i = 0; i < n; i++) {
enemy_x[i] += enemy_move[i];
if ((enemy_x[i] < 0) || (enemy_x[i] > (dim.width - enemy_width))) {
enemy_move[i] = -enemy_move[i];
}
}
}
private void updateMyPosition() {
if (my_x < 0) {
my_x = 800;
}
if (my_x > 800) {
my_x = 0;
}
}
private void activateMyMissile() {
//shoot a missile
if (missile_flag == 0) {
my_missile_x = my_x + player_width / 2;
my_missile_y = MY_Y; //MY_Y=400
missile_flag = 1;
}
}
private void updateMyMissile() {
//update missile position if alive
if (missile_flag == 1) {
my_missile_y -= 15;
if (0 > my_missile_y) {
missile_flag = 0;
}
}
}
private void activateEnemiesMissile() {
//activate enemies' missile if enemy is alive and its missile is not alive
for (int i = 0; i < n; i++) {
if (enemy_alive[i] == 1 && e_missile_flag[i] == 0) {
e_missile_x[i] = enemy_x[i] + enemy_width / 2;
e_missile_y[i] = enemy_y[i];
e_missile_flag[i] = 1;
}
}
}
private void updateEnemiesMissile() {
//update enemies' missile position if alive
Dimension dim = getSize();
for (int i = 0; i < n; i++) {
if (e_missile_flag[i] == 1) {
e_missile_y[i] += e_missile_move[i];
if (e_missile_y[i] > dim.height) {
e_missile_flag[i] = 0;
}
}
}
}
private void checkHitToEnemy() {
for (int i = 0; i < n; i++) {
if (missile_flag == 1 && enemy_alive[i] == 1) {
if (my_missile_x > enemy_x[i]
&& my_missile_x < (enemy_x[i] + enemy_width)
&& my_missile_y > enemy_y[i]
&& my_missile_y < (enemy_y[i] + enemy_height)) {
//hit
missile_flag = 0;
enemy_alive[i] = 0;
}
}
}
}
private boolean checkHitToPlayer() {
for (int i = 0; i < n; i++) {
if (e_missile_flag[i] == 1) {
if (e_missile_x[i] > my_x
&& e_missile_x[i] < (my_x + player_width)
&& e_missile_y[i] > MY_Y
&& e_missile_y[i] < (MY_Y + player_height)) {
e_missile_flag[i] = 0;
return true;
}
}
}
return false;
}
private boolean checkClear() {
int cnt = 0;
for (int i = 0; i < n; i++) {
if (enemy_alive[i] == 0) {
cnt++;
}
}
return (n == cnt);
}
public void paintComponent(Graphics g) {
super.paintComponent(g); //reset graphics
Graphics2D g2d = (Graphics2D) g.create();
System.out.println(getWidth() + "x" + getHeight());
int w2 = getWidth() / 2;
int h2 = getHeight() / 2;
g2d.rotate(-Math.PI / 2, w2, h2);
g2d.setColor(Color.DARK_GRAY);
g2d.fillRect(0, 0, getWidth(), getHeight());
//draw player
g2d.setColor(Color.BLUE);
g2d.fillRect(my_x, 400, 10, 10);
// g.drawImage(image, my_x, 400, this);
//draw enemies
for (int i = 0; i < n; i++) {
if (enemy_alive[i] == 1) {
g2d.setColor(Color.RED);
g2d.fillRect(enemy_x[i], enemy_y[i], 10, 10);
// g.drawImage(image2, enemy_x[i], enemy_y[i], this);
}
}
//draw players missiles
if (missile_flag == 1) {
g2d.setColor(Color.white);
g2d.fillRect(my_missile_x, my_missile_y, 2, 5);
}
//draw enemies' missiles
for (int i = 0; i < n; i++) {
if (e_missile_flag[i] == 1) {
g2d.setColor(Color.white);
g2d.fillRect(e_missile_x[i], e_missile_y[i], 2, 5);
}
}
g2d.dispose();
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == timer) {
updateEnemiesPosition();
updateMyPosition();
updateMyMissile();
updateEnemiesMissile();
activateEnemiesMissile();
if (checkHitToPlayer()) {
System.out.println("===== Game Over =====");
System.exit(0);
}
checkHitToEnemy();
if (checkClear()) {
System.out.println("===== Game Clear =====");
System.exit(0);
}
repaint();
}
}
public void mouseClicked(MouseEvent me) {
}
public void mousePressed(MouseEvent me) {
activateMyMissile();
}
public void mouseReleased(MouseEvent me) {
}
public void mouseExited(MouseEvent me) {
}
public void mouseEntered(MouseEvent me) {
}
public void mouseMoved(MouseEvent me) {
}
public void mouseDragged(MouseEvent me) {
}
public void keyPressed(KeyEvent e) {
int key = e.getKeyCode();
switch (key) {
case KeyEvent.VK_S:
my_x = my_x + 10;
break;
case KeyEvent.VK_W:
my_x = my_x - 10;
break;
case KeyEvent.VK_DOWN:
my_x = my_x + 10;
break;
case KeyEvent.VK_UP:
my_x = my_x - 10;
break;
case KeyEvent.VK_X:
if (missile_flag == 0) {
my_missile_x = my_x + player_width / 2;
my_missile_y = MY_Y;// MY_Y=400
missile_flag = 1;
}
break;
}
}
public void keyReleased(KeyEvent e) {
}
public void keyTyped(KeyEvent e) {
}
}
}
Also, beware, transformations of this nature are accumulative. You should, instead, take a snapshot of the Graphics context and dispose of it once you're done (see the above for an example).
Also, have look at How to Use Key Bindings as it will help resolve the focus issues related to KeyListener

2d array of objects

im really new in Java. I just need to explain how to declare 2D array of objects, i have something like:
package breakout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.Color;
import java.awt.Font;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JOptionPane;
public class Breakout extends JPanel {
public class Ball {
private
int x = 400;
int y = 300;
int speed = 2;
int dirx = 1;
int diry = -1;
public
void bounce(int px, int py, int lx, int ly) {
if ((x + 10 >= 800 && dirx == 1) || (x <= 0 && dirx == -1))
dirx *= -1;
if (y <= 0 && diry == -1)
diry *= -1;
if (y + 10 >= py && y <= py + ly && diry == 1 && x + 10 >= px && x <= px + lx)
diry *= -1;
}
int getX() {
return x;
}
int getY() {
return y;
}
void setDirx(){
dirx *= -1;
}
void setDiry(){
diry *= -1;
}
void move() {
x += speed*dirx;
y += speed*diry;
}
void paint(Graphics2D g) {
g.fillOval(x,y,10,10);
}
}
public class Paddle {
private
int x = 400;
int y = 520;
int width = 100;
int height = 6;
int speed = 6;
int dirL = 0;
int dirR = 0;
public
void move() {
x -= speed*dirL;
x += speed*dirR;
}
void stop() {
if (x <= 0)
x = 0;
if (x + width >= 800)
x = 800 - width;
}
int getX() {
return x;
}
int getY() {
return y;
}
int getWidth() {
return width;
}
int getHeight() {
return height;
}
void paint(Graphics2D g) {
g.fillRect(x,y,width,height);
}
public void keyReleased(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_LEFT)
dirL = 0;
else if (e.getKeyCode() == KeyEvent.VK_RIGHT)
dirR = 0;
else {
dirL = 0;
dirR = 0;
}
}
public void keyPressed(KeyEvent e) {
switch(e.getKeyCode()) {
case KeyEvent.VK_LEFT:
dirL = 1;
break;
case KeyEvent.VK_RIGHT:
dirR = 1;
break;
}
}
}
public class Brick {
private
int x;
int y;
int width;
int height;
boolean alive;
boolean inX = false,inY = false;
public
void setUpBrick(int px, int py, int w, int h, boolean al) {
x = px;
y = py;
width = w;
height = h;
alive = al;
}
void setAlive(boolean alive) {
this.alive = alive;
}
void paint(Graphics2D g) {
if (alive)
g.fillRect(x,y,width,height);
}
boolean collision(int bx, int by) {
if (alive) {
if (bx + 10 >= x && bx <= x + width && by + 10 >= y && by <= y + height) {
setAlive(false);
return true;
} else return false;
}
else return false;
}
void inAreaX(int bx) {
if (bx + 10 >= x && bx <= x + width) {
System.out.println("inAreaX");
inX = true;
} else {
inX = false;
}
}
void inAreaY(int by) {
if (by + 10 >= y && by <= y + height) {
System.out.println("inAreaY");
inY = true;
} else {
inY = false;
}
}
boolean isInAreaX () {
if (inX)
return true;
else return false;
}
boolean isInAreaY () {
if (inY)
return true;
else return false;
}
}
Ball ball = new Ball();
Paddle paddle = new Paddle();
Brick[][] brick = new Brick[8][4];
for (int i = 0; i < 8; i++) {
for (int j = 0; j < 4; j++) {
brick[i][j].setUpBrick(j * 101, i * 51, 100, 50, true);
}
}
void bounce() {
for (int i = 0; i < 8; i++) {
for (int j = 0; j < 4; j++) {
brick[i][j].inAreaX(ball.getX());
brick[i][j].inAreaY(ball.getY());
if (brick[i][j].collision(ball.getX(), ball.getY())) {
if (brick[i][j].isInAreaX()) {
ball.setDiry();
} else if (brick[i][j].isInAreaY()) {
ball.setDirx();
}
}
}
}
}
void move() {
ball.bounce(paddle.getX(), paddle.getY(), paddle.getWidth(),paddle.getHeight());
ball.move();
paddle.move();
paddle.stop();
bounce();
}
public Breakout() {
addKeyListener(new KeyListener() {
public void keyTyped(KeyEvent e) {
}
public void keyReleased(KeyEvent e) {
paddle.keyReleased(e);
}
public void keyPressed(KeyEvent e) {
paddle.keyPressed(e);
}
});
setFocusable(true);
}
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setColor(Color.RED);
ball.paint(g2d);
g2d.setColor(Color.BLACK);
paddle.paint(g2d);
g2d.setColor(Color.ORANGE);
for (int i = 0; i < 8; i++)
for (int j = 0; j < 4; j++)
brick[i][j].paint(g2d);
}
public static void main(String[] args) throws InterruptedException {
JFrame window = new JFrame("Tennis");
Breakout game = new Breakout();
window.add(game);
window.setSize(800,600);
window.setVisible(true);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
while (true) {
game.move();
game.repaint();
Thread.sleep(10);
}
}
i need to inicialize 2d array of brick, but it says that first for is unexpected token. How to write it? Thank you.

Unless if I have miscounted your opening and closing braces, your for loop is not inside any method, it's directly in your class body. That's why you're getting unexpected token. You will probably want to move it into the Breakout constructor.

In order to create a 2D array in Java, you can create such an array like this:
Object testArray = new Object[10][10];
This array is now a 10*10 array with memory allocated for 100 Object references.
You can create pointers two Objects with a double for-loop:
for (int i = 0; i < testArray.length(); i++) {
for (int j = 0; j < testArray.length; j++) {
testArray[i][j] = Object; //here you input the objects that you want to point to
}
}

Move the logic from setUpBrick to a constructor.
public class Brick {
private int x;
private int y;
private int width;
private int height;
private boolean alive;
private boolean inX = false,inY = false;
public Brick(int px, int py, int w, int h, boolean al) {
x = px;
y = py;
width = w;
height = h;
alive = al;
}
...
}
Then change
brick[i][j].setUpBrick(j * 101, i * 51, 100, 50, true);
to
brick[i][j] = new Brick(j*101, i*51, 100, 50, true);
Also note that access modifiers don't apply to a whole section of your class. In your example,
private
int x;
int y;
int width;
int height;
boolean alive;
boolean inX = false,inY = false;
means that only x is going to be private. The rest of the members will get the default access modifier.
One more tip. A couple of your methods can be simplified.
boolean isInAreaY () {
if (inY)
return true;
else return false;
}
can be written as:
boolean isInAreaY() {
return inY;
}

Java Tetris rotation bug

I'm having some problems with Tetris. So first of all, I have a class Shape, and then subclasses of Shape for each shape type. This is how a Shape subclass looks like:
public class SquareShape extends Shape {
public SquareShape(){
coords = squareShapeCoords;
shape = SQUARESHAPE;
}
}
In the Shape class I have a rotate method as follows:
protected void setX(int i, int x) { coords[i][0] = x; }
protected void setY(int i, int y) { coords[i][1] = y; }
public int x(int i) { return coords[i][0]; }
public int y(int i) { return coords[i][1]; }
public Shape rotate(){
if (this.getShape().equals(SQUARESHAPE)) return this;
Shape newShape = new Shape();
newShape.shape = this.shape;
for (int i = 0; i < 4; i++) {
newShape.setX(i, y(i));
newShape.setY(i, -x(i));
}
return newShape;
}
Note that I store the coordinates of each shape in 2D arrays.
Also, this is my game engine class:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class GameEngine extends JPanel implements ActionListener{
private final int HEIGHT = 15;
private final int WIDTH = 10;
private int score;
int coordX = 0;
int coordY = 0;
Timer timer;
boolean isFinishedFalling = false;
boolean isRunning = false;
boolean isPaused = false;
Shape block;
String[] shapes;
public GameEngine(){
setFocusable(true);
block = new Shape();
timer = new Timer(600, this);
timer.start();
addMouseListener(new MAdapter());
addMouseWheelListener(new WheelAdapter());
addKeyListener(new KAdapter());
setBackground(Color.BLACK);
shapes = new String[WIDTH * HEIGHT];
clearShapes();
}
int squareWidth() { return (int) getSize().getWidth() / WIDTH; }
int squareHeight() { return (int) getSize().getHeight() / HEIGHT; }
String shapeAt(int x, int y) { return shapes[(y * WIDTH) + x]; }
public int getScore() {return score;}
public void actionPerformed(ActionEvent e){
if(isFinishedFalling){
isFinishedFalling = false;
newBlock();
} else moveDown();
}
private boolean move(Shape newShape, int newCoordX, int newCoordY)
{
for (int i = 0; i < 4; ++i) {
int x = newCoordX + newShape.x(i);
int y = newCoordY - newShape.y(i);
if (x < 0 || x >= WIDTH || y < 0 || y >= HEIGHT) return false;
if (!shapeAt(x, y).equals(Shape.DEFAULTSHAPE)) return false;
}
block = newShape;
coordX = newCoordX;
coordY = newCoordY;
repaint();
return true;
}
private boolean moveLeft() { return move(block, coordX-1, coordY);}
private boolean moveRight() { return move(block, coordX+1, coordY);}
private boolean moveDown(){
if(!move(block, coordX, coordY-1)){
blockIsDown();
return false;
} else return true;
}
private void dropDown(){
int y = coordY;
while(y>0){
if(!move(block, coordX, y-1)) break;
y -= 1;
}
blockIsDown();
}
private boolean rotate() { return move(block.rotate(), coordX, coordY);}
private void blockIsDown(){
for(int i=0; i<4; i++){
int a = coordX + block.x(i);
int b = coordY - block.y(i);
shapes[b * WIDTH + a] = block.getShape();
}
clearFullLines();
if(!isFinishedFalling) newBlock();
}
private void clearFullLines(){
int fullLines = 0;
for(int i = HEIGHT-1; i>=0; i--){
boolean lineFull = true;
for(int j=0; j<WIDTH; j++){
if(shapeAt(j, i).equals(Shape.DEFAULTSHAPE)){
lineFull = false;
break;
}
}
if(lineFull){
fullLines++;
for(int m=i; m<HEIGHT-1; m++){
for(int n=0; n<WIDTH; n++)
shapes[(m*WIDTH) + n] = shapeAt(n, m+1);
}
}
}
if(fullLines>0){
score += fullLines*100;
isFinishedFalling = true;
block.setShape(Shape.DEFAULTSHAPE);
repaint();
}
}
private void newBlock()
{
block = new RandomShape();
coordX = WIDTH / 2 + 1;
coordY = HEIGHT - 1 + block.minY();
if (!move(block, coordX, coordY)) {
block.setShape(Shape.DEFAULTSHAPE);
timer.stop();
isRunning = false;
}
}
private void clearShapes(){
for(int i=0; i< WIDTH * HEIGHT; i++) shapes[i] = Shape.DEFAULTSHAPE;
}
private void drawSquare(Graphics g, int x, int y, String shape){
Color color = Color.BLACK;
if(shape.equals(Shape.ZSHAPE)) color = Color.GREEN;
if(shape.equals(Shape.SSHAPE)) color = Color.RED;
if(shape.equals(Shape.LINESHAPE)) color = Color.CYAN;
if(shape.equals(Shape.TSHAPE)) color = Color.BLUE;
if(shape.equals(Shape.SQUARESHAPE)) color = Color.YELLOW;
if(shape.equals(Shape.LSHAPE)) color = Color.MAGENTA;
if(shape.equals(Shape.MIRROREDLSHAPE)) color = Color.ORANGE;
g.setColor(color);
g.fillRect(x + 1, y + 1, squareWidth() - 2, squareHeight() - 2);
g.setColor(color.brighter());
g.drawLine(x, y + squareHeight() - 1, x, y);
g.drawLine(x, y, x + squareWidth() - 1, y);
g.setColor(color.darker());
g.drawLine(x + 1, y + squareHeight() - 1, x + squareWidth() - 1, y + squareHeight() - 1);
g.drawLine(x + squareWidth() - 1, y + squareHeight() - 1, x + squareWidth() - 1, y + 1);
}
public void paint(Graphics g){
super.paint(g);
Dimension size = getSize();
int top = (int) size.getHeight() - HEIGHT * squareHeight();
for(int i=0; i<HEIGHT; i++){
for(int j=0; j<WIDTH; j++){
String s = shapeAt(j, HEIGHT-i-1);
if(!s.equals(Shape.DEFAULTSHAPE))
drawSquare(g, j * squareWidth(), top + i * squareHeight(), s);
}
}
if(!block.getShape().equals(Shape.DEFAULTSHAPE)){
for(int i=0; i<4; i++){
int x = coordX + block.x(i);
int y = coordY - block.y(i);
drawSquare(g, x * squareWidth(), top + (HEIGHT - y - 1) * squareHeight(), block.getShape());
}
}
}
public void start(){
if(isPaused) return;
isRunning = true;
isFinishedFalling = false;
score = 0;
clearShapes();
newBlock();
timer.start();
}
private void pause(){
if(!isRunning) return;
isPaused = !isPaused;
if(isPaused){
timer.stop();
} else{
timer.start();
}
repaint();
}
class MAdapter extends MouseAdapter{
public void mouseClicked(MouseEvent e){
if (!isRunning || block.getShape().equals(Shape.DEFAULTSHAPE) || isPaused) return;
int buttonPressed = e.getButton();
if(buttonPressed == MouseEvent.BUTTON1) moveLeft();
if(buttonPressed == MouseEvent.BUTTON2) rotate();
if(buttonPressed == MouseEvent.BUTTON3) moveRight();
}
}
class WheelAdapter implements MouseWheelListener{
public void mouseWheelMoved(MouseWheelEvent e){
if (!isRunning || block.getShape().equals(Shape.DEFAULTSHAPE) || isPaused) return;
int wheelRotation = e.getWheelRotation();
if(wheelRotation == 1) moveDown();
if(wheelRotation == -1) dropDown();
}
}
class KAdapter extends KeyAdapter{
public void keyPressed(KeyEvent e){
if (!isRunning || block.getShape().equals(Shape.DEFAULTSHAPE) || isPaused) return;
int key = e.getKeyCode();
if(key == KeyEvent.VK_SPACE) pause();
}
}
}
My problem is the following: When I try to rotate the blocks, it works good the first time, but it messes up completely if I try to rotate them a second time.
This is supposed to be my line shape:
And this is my L shape (the yellow one):
Note that this isn't just a graphical bug, the game treats the elements as one single square, or two respectively.
I've been looking for hours at my code to see what the problem could be, but I had no luck. Any help would be appreciated

Thank you for the replies, but after further investigation, I found out what the problem was.
The problem was with the rotate method:
public Shape rotate(){
if (this.getShape().equals(SQUARESHAPE)) return this;
Shape newShape = new Shape();
newShape.shape = this.shape;
for (int i = 0; i < 4; i++) {
newShape.setX(i, -y(i));
newShape.setY(i, x(i));
}
return newShape;
}
I added to the mouse adapter the following code to see what happens with the coordinates of the current block:
if(buttonPressed == MouseEvent.BUTTON2) {
System.out.println(Arrays.deepToString(block.getCoords()));
rotate();
}
This is the output for the SShape:
[[0, -1], [0, 0], [1, 0], [1, 1]]
[[1, 0], [0, 0], [0, 1], [-1, 1]]
[[0, 0], [0, 0], [-1, -1], [-1, -1]]
[[0, 0], [0, 0], [1, 1], [1, 1]]
[[0, 0], [0, 0], [-1, -1], [-1, -1]]
[[0, 0], [0, 0], [1, 1], [1, 1]]
[[0, 0], [0, 0], [-1, -1], [-1, -1]]
The first line contains the initial coordinates I gave for the SShape. The second line contains the modified coordinates, after the rotate() method. As you can see, X takes the -Y value and Y takes the X value. In the third line however, X takes the -Y value, but Y takes the updated X value instead of the previous one, so X = Y from the third line onwards. To solve this problem, I made an array to hold the values of X before updating it, as follows:
public Shape rotate(){
if (this.getShape().equals(SQUARESHAPE)) return this;
Shape newShape = new Shape();
newShape.shape = this.shape;
int[] oldX = {this.x(0), this.x(1), this.x(2), this.x(3)};
for (int i = 0; i < 4; i++) {
newShape.setX(i, -y(i));
newShape.setY(i, oldX[i]);
}
return newShape;
}

Remove the rotate method, add a hard-coded rotation array each shape and all 4 rotations. First index should be the rotation index (0-3)
then add a member variable to the shape base class and change rotation to something like:
public void rotate(Boolean rotateRight) {
if (rotateRight) {
rotation++;
else {
rotation--;
}
if (rotation < 0) {
rotation = 3;
}
if (rotation > 3) {
rotation = 0;
}
}
Then make some new function like
public int[][] getCurrentRotation() {
return shapeMatrix[rotation];
}
and use this int[][] (or int[] if you want to flatten the array) to draw the appropriate squares

Java Tetris - Confused on grid[row][col] and coordinates (x, y)

I'm making Tetris in java for fun... I pretty much had everything working... but later found out that when I wanted to change the dimensions so it was square ([10 row][10 col] matrix, but instead a [12 row][10 col] matrix), that I started getting Index Out of Bound exceptions... see here: Java Tetris - weird row clearing issue
So I tried fixing everything so that the rows and columns weren't flip flopped... But am now getting hung up on the fact that the grid takes [row][col], but I’m moving around the tiles as (x, y) coordinates…
What’s confusing me is that row = y and col = x… which is reversed… so when I pass in coordinates I’m not sure when to swap them.
I know it’s a simple thing, but it’s confusing the hell out of me and I keep getting out of bounds exceptions whenever I think I have it right.
I'm not sure where the exact issue is, so I'm posting a full Sscce of my program... I think the issue is in the Board class...
Here, the block should still be able to move down... but if it tries to go down further than this...
I get:
Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 10
at Board.getTileAt(Board.java:177)
at Tile.collision(Tile.java:31)
at Piece.isCollision(Piece.java:172)
at Board.collisionCheck(Board.java:192)
at Piece.movePieceCheck(Piece.java:87)
at Board.keyPressed(Board.java:160)
Sscce:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Toolkit;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class MainSscce extends JPanel {
static MainSscce runMe;
BoardSscce gameBoard, scoreBoard;
public MainSscce() { //creates a new frame window and sets properties
JFrame f = new JFrame("Tetris");
//width (height), length, tilesize
gameBoard = new BoardSscce(12, 10, 35);
// scoreBoard = new BoardSscce(10, 10, 35);
f.add(gameBoard);
f.setSize(gameBoard.getWidth(), gameBoard.getHeight());
f.setVisible(true);
f.setResizable(false);
f.setVisible(true);
f.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
Dimension screensize = Toolkit.getDefaultToolkit().getScreenSize();
//set j frame location to appear in middle of screen
f.setLocation( (screensize.width - f.getWidth())/2,
(screensize.height - f.getHeight())/2-100 );
}
public static void main(String[] args) {
runMe = new MainSscce();
}
}
import java.awt.Graphics;
import java.awt.Color;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JPanel;
import javax.swing.Timer;
import java.awt.event.*; // for ActionListener and ActionEvent
import java.util.Random;
public class BoardSscce extends JPanel implements KeyListener {
private TileSscce grid[][];
private int totalRows, totalCols, tilesize, level, totalScore;
private final int changeLevelMultiplier;
private PieceSscce newPiece, nextPiece;
private String randomPiece;
private boolean gameLost;
public BoardSscce(int r, int c, int ts) {
totalRows = r;
totalCols = c;
tilesize = ts;
//set grid size to [# rows][# columns], aka [height][width]
grid = new TileSscce[totalRows][totalCols];
gameLost = false;
System.out.println("TotalRows: " + totalRows + ", " + "TotalCols: " + totalCols);
//multiplier to determine what score the level changes, which is:
//level * changeLevelMultiplier;
changeLevelMultiplier = 40;
//initialize score to 0
totalScore = 0;
//initialize level to 0
level = 0;
newPiece = new PieceSscce(this, randomPiece(), getColor());
addKeyListener(this);
setFocusable(true);
//getTranspose();
timer();
}
public String randomPiece() {
String[] Pieces = {"L", "O", "Z", "RevZ", "Bar", "T", "RevL"};
int rand = (int) (Math.random() * Pieces.length);
randomPiece = Pieces[rand];
return randomPiece;
}
public Color getColor() {
Color color;
if (randomPiece.equals("L"))
color = new Color(17, 255, 0);
else if(randomPiece.equals("O"))
color = new Color(117, 168, 255);
else if(randomPiece.equals("Z"))
color = new Color(255, 187, 82);
else if(randomPiece.equals("RevZ"))
color = new Color(206, 27, 72);
else if(randomPiece.equals("Bar"))
color = new Color(50, 216, 219);
else if(randomPiece.equals("T"))
color = new Color(252, 148, 240);
else
color = new Color(255, 255, 52);
//Random rand = new Random();
//float r = rand.nextFloat();
//float g = rand.nextFloat();
//float b = rand.nextFloat();
//Color randomColor = new Color(r, g, b);
return color;
}
//dimensions of board = width * tilesize
public int getWidth() {
return totalCols * tilesize;
}
public int getHeight() {
return totalRows * tilesize;
}
public int getTileSize() {
return tilesize;
}
public void paintComponent(Graphics g) {
g.setColor(Color.black);
g.fillRect(0, 0, getWidth(), getHeight());
for(int row = 0; row < grid.length; row++) {
for(int col = 0; col < grid[row].length; col++) {
//System.out.println(row + ", " + col);
g.drawString("[" + row + "][" + col + "]", col * tilesize, row * tilesize+10);
System.out.println(row + ", " + col);
//if there is a non-null space, that is a Tetris piece... fill it
if(grid[row][col] != null) {
g.setColor(grid[row][col].getColor());
g.fillRect(row * tilesize, col * tilesize, tilesize, tilesize);
g.setColor(Color.WHITE);
}
}
}
// g.drawString("Level: " + level, this.getWidth()/2, this.getHeight()/2-130);
// g.drawString("Score: " + totalScore, this.getWidth()/2, this.getHeight()/2-100);
if (gameLost == true) {
g.drawString("Way to go, loser...", this.getWidth()/2, this.getHeight()/2);
messageTimer();
}
}
//Auto move piece
public void timer () {
int interval;
switch (level) {
//each level increases drop speed by .10 seconds
case 1: interval = 800;
break;
case 2: interval = 700;
break;
case 3: interval = 600;
break;
case 4: interval = 500;
break;
default: interval = 1000;
break;
}
Timer t = new Timer(interval, new ActionListener() {
public void actionPerformed(ActionEvent e) {
//newPiece.autoMove();
//repaint();
}
});
t.start();
}
public void messageTimer() {
Timer t = new Timer(5000, new ActionListener() {
public void actionPerformed(ActionEvent e) {
gameLost = false;
}
});
t.start();
}
//move piece on key input
public void keyPressed(KeyEvent e) {
newPiece.movePieceCheck(e.getKeyCode());
repaint();
}
public void keyReleased(KeyEvent e) {
}
public void keyTyped(KeyEvent e) {
}
public boolean isValidCoordinate(int x, int y) {
return x >= 0 && y >= 0 && x < totalCols && y < totalRows;
}
// returns the tile at (x, y) or null if empty
public Tile getTileAt(int x, int y) {
if(isValidCoordinate(x, y))
return grid[x][y];
return null;
}
// sets the tile at (x, y) to tile
public void setTileAt(Tile tile, int x, int y) {
if(isValidCoordinate(x, y))
grid[x][y] = tile;
}
public boolean isOpen(int x, int y) {
return isValidCoordinate(x, y) && (getTileAt(x, y) == null);
}
public void collisionCheck() {
if (newPiece.isCollision()){
newPiece = new PieceSscce(this, randomPiece(), getColor());
}
}
public void changeLevel () {
int max = (level+1)*changeLevelMultiplier;
if (totalScore >= max) {
System.out.println(max + "reached... next level");
level++;
totalScore = 0;
timer();
}
}
public int tallyScore(int totalLines) {
int score = 0;
switch (totalLines) {
case 1: score = 40 * (level + 1);
break;
case 2: score = 100 * (level + 1);
break;
case 3: score = 300 * (level + 1);
break;
case 4: score = 1200 * (level + 1);
break;
default: break;
}
return score;
}
//loop through all rows starting at bottom (12 rows)
public void checkBottomFull() {
int lines = 0;
for(int row = 12; row > 0; row--) {
/* while (isFull(row)) {
lines++;
// clearRow(row);
}*/
}
totalScore += tallyScore(lines);
//check if level needs to be changed based on current score...
changeLevel();
//reset lines after score has been incremented
lines=0;
}
//loop through all columns in that row (10 columns)
public boolean isFull(int row) {
for (int col = 0; col <= 10; col++) {
System.out.println(row + ", " + col);
if(grid[row][col] == null) {
return false;
}
}
return true;
}
public void clearRow(int rowToClear) {
for(int row = rowToClear; row > 0; row--) {
for(int col = 0; col < grid[row].length; col++) {
grid[col][row] = grid[col][row-1];
}
}
}
public void checkEndGame(int x, int y) {
//if currPiece y location = 0 AND the space below is filled...
if (y <= 2 && !isOpen(x, y+1)) {
gameLost = true;
level = 0;
totalScore = 0;
//reset timer
timer();
for(int row = 0; row < grid.length; row++) {
for(int col = 0; col < grid[row].length; col++) {
grid[row][col] = null;
}
}
}
}
}
import java.awt.Color;
import java.awt.event.KeyEvent;
public class PieceSscce {
public int[] pieceCoordinates;
public String shape, currRotation;
public Color color;
public BoardSscce board;
public int rotationsCounter;
public TileSscce tile[];
public int[] newPositionX, newPositionY, currPositionX, currPositionY;
//don't need to pass in board because I'm already utilizing the Tiles class, which knows about the board
public Piece(Board b, String randomPiece, Color randomColor) {
shape = randomPiece;
color = randomColor;
board = b;
newPositionX = new int[4];
newPositionY = new int[4];
currPositionX = new int[4];
currPositionY = new int[4];
pieceCoordinates = new int[8];
//set pieceCoordinates global variable
getShape(shape);
tile = new TileSscce[4];
int counterX = 0, counterY = 1;
System.out.print("\"" + shape + "\" Coordinates: ");
//generate 4 new Tiles at specified coordinates that will compose the Piece
for (int i = 0; i < tile.length; i++) {
tile[i] = new TileSscce(board, pieceCoordinates[counterX], pieceCoordinates[counterY]);
System.out.print("(" + pieceCoordinates[counterX] + ", " + pieceCoordinates[counterY] + ") ");
//increment by 2 because x,y values are next to each other in array
counterX+=2;
counterY+=2;
}
System.out.println("\n");
for (int i = 0; i < tile.length; i++) {
tile[i].setColor(color);
}
}
public void calcNewPosition(int newX, int newY, int currTile) {
newPositionX[currTile] = newX;
newPositionY[currTile] = newY;
}
public void clearCurrPosition() {
for (int i = 0; i < tile.length; i++) {
currPositionX[i] = tile[i].getX();
currPositionY[i] = tile[i].getY();
board.setTileAt(null, currPositionX[i], currPositionY[i]);
}
}
public void autoMove() {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getX(), tile[i].getY()+1, i);
}
clearCurrPosition();
for (int i = 0; i < tile.length; i++) {
board.checkEndGame(tile[i].getX(), tile[i].getY());
System.out.println("Checking..." + tile[i].getX() + ", " + tile[i].getY());
}
board.checkBottomFull();
board.collisionCheck();
move();
}
public void movePieceCheck(int keycode) {
if (keycode == KeyEvent.VK_DOWN) {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getX(), tile[i].getY()+1, i);
}
clearCurrPosition();
for (int i = 0; i < tile.length; i++) {
board.checkEndGame(tile[i].getX(), tile[i].getY());
System.out.println("Checking..." + tile[i].getX() + ", " + tile[i].getY());
}
board.checkBottomFull();
board.collisionCheck();
move();
}
if (keycode == KeyEvent.VK_RIGHT) {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getX()+1, tile[i].getY(), i);
}
clearCurrPosition();
move();
}
if (keycode == KeyEvent.VK_LEFT) {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getX()-1, tile[i].getY(), i);
}
clearCurrPosition();
move();
}
//rotate left
if (keycode == KeyEvent.VK_A) {
int[] rotatedCoords = calcRotation("left");
clearCurrPosition();
rotate(rotatedCoords, "left");
}
//rotate right
if (keycode == KeyEvent.VK_D) {
int[] rotatedCoords = calcRotation("right");
clearCurrPosition();
rotate(rotatedCoords, "right");
}
}
public boolean movePieceValid() {
boolean valid = true;
for (int i = 0; i < tile.length; i++) {
if(!tile[i].checkNewLocation(newPositionX[i], newPositionY[i]))
valid = false;
}
return valid;
}
public boolean validRotation(int[] rotatedCoordinates) {
boolean valid = true;
int counterX = 0, counterY = 1;
for (int i = 0; i < tile.length; i++) {
if(!tile[i].checkNewLocation(rotatedCoordinates[counterX], rotatedCoordinates[counterY]))
valid = false;
counterX +=2;
counterY +=2;
}
return valid;
}
public void move() {
if (movePieceValid()) {
for (int i = 0; i < tile.length; i++) {
tile[i].setLocation(newPositionX[i], newPositionY[i]);
}
} else {
for (int i = 0; i < tile.length; i++) {
tile[i].setLocation(currPositionX[i], currPositionY[i]);
}
}
}
public void rotate(int[] rotatedCoordinates, String rotation) {
int counterX = 0, counterY = 1;
if (validRotation(rotatedCoordinates)) {
for (int i = 0; i < tile.length; i++) {
tile[i].setLocation(rotatedCoordinates[counterX], rotatedCoordinates[counterY]);
counterX+=2;
counterY+=2;
}
//else, if not valid move set the original location
} else {
for (int i = 0; i < tile.length; i++) {
tile[i].setLocation(currPositionX[i], currPositionY[i]);
}
}
}
public boolean isCollision() {
boolean collision = false;
for (int i = 0; i < tile.length; i++) {
if(tile[i].collision(newPositionX[i], newPositionY[i])) {
collision = true;
}
}
return collision;
}
//calc curr coordinates, send them to getRotation... which will create new piece based on coords
public int[] calcRotation(String direction) {
for (int i = 0; i < tile.length; i++) {
currPositionX[i] = tile[i].getX();
currPositionY[i] = tile[i].getY();
System.out.println("Current position: (" + currPositionX[i] + "," + currPositionY[i]+")");
}
return getRotation(currPositionX, currPositionY, direction);
}
public int[] getRotation (int coordinatesX[], int coordinatesY[], String direction) {
int[] rotationDirection;
int[] coordinates = new int[8];
int[] origin = new int[2];
int[] newCoordinates = new int[8];
int[] resultCoordinates = new int[8];
int[] finalCoordinates = new int[8];
int vectorMatrix[][] = new int[2][4];
//set either R(90) or R(-90) rotation matrix values:
if (direction.equals("right")) {
rotationDirection = new int[] {0, -1, 1, 0};
}
else {
rotationDirection = new int[] {0, 1, -1, 0};
}
int counterX = 0, counterY = 1, x = 0;
while (counterY < coordinates.length) {
//add arrays coordinatesX and coordinatesY into a single array: coordinates
coordinates[counterX] = coordinatesX[x];
coordinates[counterY] = coordinatesY[x];
counterX+=2;
counterY+=2;
x++;
}
//set origin so it rotates around center...
if (shape.equals("RevZ")) {
origin[0] = coordinates[6];
origin[1] = coordinates[7];
}
else if (shape.equals("T")) {
origin[0] = coordinates[4];
origin[1] = coordinates[5];
}
else {
origin[0] = coordinates[2];
origin[1] = coordinates[3];
}
//subtract origin from vectors
System.out.println();
counterX = 0;
counterY = 1;
while (counterY < newCoordinates.length) {
//System.out.println(coordinates[counterX] + ", " + coordinates[counterY]);
newCoordinates[counterX] = coordinates[counterX] - origin[0];
newCoordinates[counterY] = coordinates[counterY] - origin[1];
System.out.println("Translated coordinates: (" + newCoordinates[counterX] + ", " + newCoordinates[counterY] + ")");
counterX+=2;
counterY+=2;
}
System.out.println();
System.out.println("vector matrix:");
//fill up vectorMatrix with coordinates
int k = 0;
for (int col = 0; col < 4; col++) {
for (int row = 0; row < 2; row++) {
vectorMatrix[row][col] = newCoordinates[k++];
}
}
//print vectorMatrix:
for (int i = 0; i < vectorMatrix.length; i++) {
System.out.print("[");
for (int j = 0; j < vectorMatrix[i].length; j++) {
System.out.print(vectorMatrix[i][j]);
}
System.out.println("]");
}
int rotationMatrix[][] = new int[2][2];
//fill up rotationMatrix
System.out.println();
System.out.println("multiplicative matrix:");
k = 0;
for (int row = 0; row < 2; row++) {
System.out.print("[");
for (int col = 0; col < 2; col++) {
rotationMatrix[row][col] = rotationDirection[k++];
System.out.print(rotationMatrix[row][col]);
}
System.out.println("]");
}
//perform matrix multiplication
int[][] result = multiplyMatrices(rotationMatrix, vectorMatrix);
//print resulting matrix
System.out.println();
System.out.println("result matrix:");
for (int i = 0; i < result.length; i++) {
System.out.print("[");
for (int j = 0; j < result[i].length; j++) {
System.out.print(result[i][j]);
}
System.out.println("]");
}
//load new matrix coordinates back into array
k = 0;
for (int col = 0; col < 4; col++) {
for (int row = 0; row < 2; row++) {
resultCoordinates[k] = result[row][col];
k++;
}
}
System.out.println();
System.out.println("result coordinates:");
counterX = 0;
counterY = 1;
while (counterY < resultCoordinates.length) {
finalCoordinates[counterX] = resultCoordinates[counterX] + origin[0];
finalCoordinates[counterY] = resultCoordinates[counterY] + origin[1];
System.out.print("("+finalCoordinates[counterX] + ", " + finalCoordinates[counterY]+")");
counterX+=2;
counterY+=2;
}
return finalCoordinates;
}
public int[][] multiplyMatrices(int rotationMatrix[][], int vectorMatrix[][]) {
int mA = rotationMatrix.length;
int nA = rotationMatrix[0].length;
int mB = vectorMatrix.length;
int nB = vectorMatrix[0].length;
if (nA != mB) throw new RuntimeException("Illegal matrix dimensions.");
int[][] C = new int[mA][nB];
for (int i = 0; i < mA; i++) {
for (int j = 0; j < nB; j++) {
for (int k = 0; k < nA; k++) {
C[i][j] += (rotationMatrix[i][k] * vectorMatrix[k][j]);
}
}
}
return C;
}
public int[] getShape(String shape) {
if (shape.equals("L")) {
//pieceCoordinates = new int[] {0, 1, 0, 2, 1, 2, 2, 2};
pieceCoordinates = new int[] {4, 0, 4, 1, 5, 1, 6, 1};
}
else if (shape.equals("O")) {
pieceCoordinates = new int[] {0, 1, 1, 1, 0, 2, 1, 2};
}
else if (shape.equals("Z")) {
pieceCoordinates = new int[] {0, 1, 1, 1, 1, 2, 2, 2};
}
else if (shape.equals("RevZ")) {
pieceCoordinates = new int[] {1, 1, 2, 1, 0, 2, 1, 2};
}
else if (shape.equals("Bar")) {
//pieceCoordinates = new int[] {0, 1, 1, 1, 2, 1, 3, 1};
pieceCoordinates = new int[] {0, 1, 1, 1, 2, 1, 3, 1};
}
else if (shape.equals("T")) {
pieceCoordinates = new int[] {1, 1, 0, 2, 1, 2, 2, 2};
}
else if (shape.equals("RevL")) {
pieceCoordinates = new int[] {0, 2, 1, 2, 2, 2, 2, 1};
}
return pieceCoordinates;
}
}
import java.awt.Color;
import java.util.Random;
public class TileSscce {
private BoardSscce board;
private int currX, currY;
private Color color;
public TileSscce(BoardSscce b, int x, int y) {
board = b;
//when Tile is instantiated, set its position
setLocation(x, y);
}
public int getX() {
return currX;
}
public int getY() {
return currY;
}
public boolean checkNewLocation(int newX, int newY) {
boolean newLocationOK = board.isOpen(newX, newY);
return newLocationOK;
}
public boolean collision(int newX, int newY) {
boolean collision = this.getY() == ((board.getHeight()/board.getTileSize()))-2 || board.getTileAt(newX, newY) != null;
return collision;
}
public void setLocation(int newX, int newY) {
// board.setTileAt(null, currX, currY);
currX = newX;
currY = newY;
board.setTileAt(this, currX, currY);
}
public Color getColor() {
return setColor(color);
}
public Color setColor(Color myColor) {
color = myColor;
return color;
}
}
Thanks!
EDIT----------
I've tried implementing both ValarDohaeris and Svend Hansen's suggestions... Now the block is moving right when I press down, up when I press left, and down when I press right...
It seems to have to do with these methods in Board class which get and set tile locations...
// returns the tile at (x, y) or null if empty
public Tile getTileAt(int row, int col) {
System.out.println("getTileAt: " + row + ", " + col);
if(isValidCoordinate(row, col))
return grid[row][col];
return null;
}
// sets the tile at (x, y) to tile
public void setTileAt(Tile tile, int row, int col) {
System.out.println("setTileAt: " + row + ", " + col);
if(isValidCoordinate(row, col))
grid[row][col] = tile;
}
And in Piece class... movements are defined as:
public void movePieceCheck(int keycode) {
if (keycode == KeyEvent.VK_DOWN) {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getRow()+1, tile[i].getCol(), i);
}
clearCurrPosition();
for (int i = 0; i < tile.length; i++) {
board.checkEndGame(tile[i].getRow(), tile[i].getCol());
}
board.checkBottomFull();
if (isCollision()) board.createNewPiece();
move();
}
if (keycode == KeyEvent.VK_RIGHT) {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getRow(), tile[i].getCol()+1, i);
}
clearCurrPosition();
move();
}
if (keycode == KeyEvent.VK_LEFT) {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getRow(), tile[i].getCol()-1, i);
}
clearCurrPosition();
move();
}

You have
grid = new TileSscce[totalRows][totalCols];
So when you want to access grid[x][y], you should check
x >= 0 && y >= 0 && x < totalRows && y < totalCols
in isValidCoordinate(x, y).

Emm... Quite interesting question. So to find out where the problem(s) may be I'll try to analyze your code a little bit...
You paste stack trace as
Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 10
at Board.getTileAt(Board.java:177)
...
and at the same time the getTileAt()
// returns the tile at (x, y) or null if empty
public Tile getTileAt(int row, int col) {
System.out.println("getTileAt: " + row + ", " + col);
if(isValidCoordinate(row, col))//isValidCoordinate()?
return grid[row][col];
return null;
}
public boolean isValidCoordinate(int x, int y) {
return x >= 0 && y >= 0 && x < totalCols && y < totalRows;
}
... so the isValidCoordinate method return terms as
x >= 0 && y >= 0 && x < totalCols && y < totalRows
...the method doesn't allow to avoid array out-of-bounds problems; Seems like you put wrong array element indexes.
A. As I can notice, you trying to put a classic math matrix on Java [][] arrays as
public void clearRow(int rowToClear) {
for(int row = rowToClear; row > 0; row--) {
for(int col = 0; col < grid[row].length; col++) {//<-- ?
grid[col][row] = grid[col][row-1];
}
}
}
... and here I must say that you should know that in [][] arrays x,y are backwards and it is y,x because :
y (or classic i) - sub-array index (vertical)
x (or classic j) - sub-array's element index (horizontal)
so you should use array index something this way grid[y][x] or grid[i][j]
As a useful tip, I recommend you to analyze your code for logic errors in this field...
B. According to your app screenshot as
... it seems like the x,y problem takes place here too because you trying to control y (vertical) coordinates but (in real) you control x (horizontal) coordinates only :S It is still because of the row,col instead of a classic Java (col,row or y,x) [][] array index positions.
C. And again concerning to the wrong directions...
...up when I press left, and down when I press right...
if (keycode == KeyEvent.VK_RIGHT) {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getRow(), tile[i].getCol()+1, i);
}
clearCurrPosition();
move();
}
Here I'll try to analyze the event as (you press right but move down)...
OK... according to one of your tasks you need to move by x coordinate (horizontally) but look closer... you make tile[i].getCol()+1 so it is newY and, of course, it moves vertically :S In your case it really moves down because you make increment as y++ ...
public void calcNewPosition(int newX, int newY, int currTile) {
newPositionX[currTile] = newX;
newPositionY[currTile] = newY;
}
public void clearCurrPosition() {
for (int i = 0; i < tile.length; i++) {
currPositionX[i] = tile[i].getX();
currPositionY[i] = tile[i].getY();
board.setTileAt(null, currPositionX[i], currPositionY[i]);
}
}
public void move() {
if (movePieceValid()) {
for (int i = 0; i < tile.length; i++) {
tile[i].setLocation(newPositionX[i], newPositionY[i]);//<-- !
}
} else {
for (int i = 0; i < tile.length; i++) {
tile[i].setLocation(currPositionX[i], currPositionY[i]);
}
}
}
...as a conclusion, I may recommend to change code (move right) something this way...
if (keycode == KeyEvent.VK_RIGHT) {
for (int i = 0; i < tile.length; i++) {
calcNewPosition(tile[i].getRow()+1, tile[i].getCol(), i);
}
clearCurrPosition();
move();
}
I hope my tips will help you to figure out what to look closer. Anyway, if you have some additional information please do comment my answer
Report if that helped you

This is based on x corresponds to columns and y corresponds to rows.
However grid is indexed by [row][col].
TileSscce grid[][] = new TileSscce[totalRows][totalCols]; // 12 => totalRows, 10 => totalCols
public int getWidth() {
return totalCols * tilesize;
}
public int getHeight() {
return totalRows * tilesize;
}
Following changes (based on your initial code - Sscce: - without later edits) will get rid of the exception and allow drawing till bottom of the board.
public void paintComponent(Graphics g) {
for (int row = 0; row < grid.length; row++) {
for (int col = 0; col < grid[row].length; col++) {
if (grid[row][col] != null) {
g.setColor(grid[row][col].getColor());
g.fillRect(col * tilesize, row * tilesize, tilesize, tilesize); // changed, check below snippet from fillRect documentation
g.setColor(Color.WHITE);
}
}
}
}
public TileSscce getTileAt(int x, int y) {
if (isValidCoordinate(x, y))
return grid[y][x]; // changed to [y][x] as grid is indexed by [row][col]
return null;
}
public void setTileAt(TileSscce tile, int x, int y) {
if (isValidCoordinate(x, y))
grid[y][x] = tile; // changed to [y][x] as grid is indexed by [row][col]
}
From fillRect documentation.
public abstract void fillRect(int x, int y, int width, int height)
The left and right edges of the rectangle are at x and x + width - 1.
The top and bottom edges are at y and y + height - 1.
This is correct.
public boolean isValidCoordinate(int x, int y) {
return x >= 0 && y >= 0 && x < totalCols && y < totalRows;
}