java如何将功能返回到主方法？
我在一节课上有一个工作程序，但我认为最好把这些课程分开，所以我把我的程序分为三节。java文件，现在程序不再运行。我在程序中的任何地方都没有一个错误，但当我尝试运行程序时，会收到此错误消息
"Exception in thread "main" java.lang.NoSuchMethodException: Tetris.main([Ljava.lang.String;)
at java.lang.Class.getMethod(Class.java:1786)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:125)"
问题是什么？如何解决
这是我的三个文件：
俄罗斯方块。java
import java.awt.*;
import java.applet.*;
import java.awt.event.*;
import java.util.Random;
import static java.awt.Color.*;
public class Tetris extends Applet {
//
// STATIC MEMBERS
//
private final static int INITIAL_DELAY = 1000;
public final static byte ROWS = 20;
public final static byte COLUMNS = 10;
public final static int EMPTY = -1;
static Color[] colors =
{black, green, blue, red,
yellow, magenta, pink, cyan};
private final static Color BACKGROUND_COLOR = Color.black;
public final static boolean PIECE_BITS[][][] = {
{
{false, true, false, false},
{false, true, false, false},
{false, true, false, false},
{false, true, false, false},
},
{
{false, false, false, false},
{false, true, true, false},
{false, true, false, false},
{false, true, false, false},
},
{
{false, false, false, false},
{false, true, false, false},
{false, true, false, false},
{false, true, true, false},
},
{
{false, false, false, false},
{false, true, false, false},
{false, true, true, false},
{false, false, true, false},
},
{
{false, false, false, false},
{false, false, true, false},
{false, true, true, false},
{false, true, false, false},
},
{
{false, false, false, false},
{false, true, false, false},
{false, true, true, false},
{false, true, false, false},
},
{
{false, false, false, false},
{false, false, false, false},
{false, true, true, false},
{false, true, true, false},
},
};
private static Random random = new Random();
//
// INSTANCE DATA
//
public static int grid[][] = new int[ROWS][COLUMNS];
public static Timer timer;
private int next_piece_grid[][] = new int[4][4];
private GridCanvas game_grid = new GridCanvas(grid, true);
private GridCanvas next_piece_canvas = new GridCanvas(next_piece_grid, false);
private TetrisPiece cur_piece;
private TetrisPiece next_piece = randomPiece();
//
// INNER CLASSES
//
private class Timer extends Thread {
private long m_delay;
private boolean m_paused = true;
private boolean m_fast = false;
private ActionListener m_cb;
public Timer(long delay, ActionListener cb) {
setDelay(delay);
m_cb = cb;
}
public void setPaused(boolean pause) {
m_paused = pause;
if (m_paused) {
} else {
synchronized (this) {
this.notify();
}
}
}
public void setDelay(long delay) {
m_delay = delay;
}
public void setFast(boolean fast) {
m_fast = fast;
if (m_fast) {
try {
this.checkAccess();
this.interrupt(); // no exception, so OK to interrupt
} catch (SecurityException se) {
}
}
}
public void run() {
while (true) {
try {
sleep(m_fast ? 30 : m_delay);
} catch (Exception e) {
}
if (m_paused) {
try {
synchronized (this) {
this.wait();
}
} catch (InterruptedException ie) {
}
}
synchronized (this) {
m_cb.actionPerformed(null);
}
}
}
} // end class Timer
private class GridCanvas extends DoubleBufferedCanvas {
private int grid[][];
public GridCanvas(int[][] grid, boolean do_background) {
this.grid = grid;
clear();
}
private void clear() {
for (int i = 0; i < grid.length; i++)
for (int j = 0; j < grid[0].length; j++)
grid[i][j] = EMPTY;
}
public Dimension getPreferredSize() {
return new Dimension(grid[0].length * 30, grid.length * 30);
}
public void paint(Graphics g) {
g = this.startPaint(g); // returned g paints into offscreen image
int width = this.getSize().width;
int height = this.getSize().height;
g.clearRect(0, 0, width, height);
int cell_size, xstart, ystart;
double panel_aspect_ratio = (double) width / height;
double grid_aspect_ratio = (double) grid[0].length / grid.length;
if (panel_aspect_ratio > grid_aspect_ratio) {
// extra space on sides
cell_size = (int) ((double) height / grid.length + 0.5);
xstart = (int) (width / 2 - (grid[0].length / 2.0 * cell_size + 0.5));
ystart = 0;
} else {
// extra vertical space
cell_size = (int) ((double) width / grid[0].length + 0.5);
xstart = 0;
ystart = (int) (height / 2 - (grid.length / 2.0 * cell_size + 0.5));
}
for (int i = 0; i < grid.length; i++) {
for (int j = 0; j < grid[0].length; j++) {
if (grid[i][j] != EMPTY) {
g.setColor(colors[grid[i][j]]);
int x = xstart + j * cell_size;
int y = ystart + i * cell_size;
g.fill3DRect(x, y, cell_size, cell_size, true);
}
}
}
this.endPaint(); // paints accumulated image in one shot
}
}
private TetrisPiece randomPiece() {
int rand = Math.abs(random.nextInt());
return new TetrisPiece(rand % (colors.length));
}
private void installNewPiece() {
next_piece_canvas.clear();
cur_piece = next_piece;
cur_piece.setPosition(3, -4); //-4 to start above top of grid
if (cur_piece.canPaste()) {
next_piece = randomPiece();
next_piece.setPosition(0, 0);
next_piece.paste(next_piece_grid);
next_piece_canvas.repaint();
} else
gameOver();
}
private void gameOver() {
System.out.println("Game Over!");
timer.setPaused(true);
}
public void start() {
timer = new Timer(INITIAL_DELAY, new ActionListener() {
public void actionPerformed(ActionEvent ae) {
synchronized (timer) {
if (cur_piece.canStepDown()) {
cur_piece.cut();
cur_piece.stepDown();
cur_piece.paste();
} else { // it hit something
timer.setFast(false);
if (!cur_piece.isTotallyOnGrid())
gameOver();
else {
installNewPiece();
}
}
}
game_grid.repaint();
}
});
timer.start();
}
public void stop() {
pauseGame();
synchronized (timer) {
timer.stop();
}
timer = null;
}
public void startGame() {
timer.setDelay(INITIAL_DELAY);
timer.setPaused(false);
}
private void pauseGame() {
timer.setPaused(true);
}
public void init() {
installNewPiece();
//create key listener for moving left, moving right
class TAdapter extends KeyAdapter {
public void keyPressed(KeyEvent e) {
int keycode = e.getKeyCode();
switch (keycode) {
case KeyEvent.VK_LEFT:
if (e.getKeyCode() == 37 || e.getKeyCode() == 38) {
int dir = e.getKeyCode() == 37 ? -1 : 1;
synchronized (timer) {
cur_piece.cut();
cur_piece.setX(cur_piece.getX() + dir);
if (!cur_piece.canPaste()) {
cur_piece.setX(cur_piece.getX() - dir);
}
}
}
}
}
}
//setting background colour and Tetrus grid
this.setLayout(new GridLayout(1, 2));
this.add(game_grid);
this.setBackground(BACKGROUND_COLOR);
this.validate();
}
public int[][] getGrid () {
return grid;
}
class DoubleBufferedCanvas extends Canvas {
private Image mActiveOffscreenImage = null;
private Dimension mOffscreenSize = new Dimension(-1, -1);
private Graphics mActiveOffscreenGraphics = null;
private Graphics mSystemGraphics = null;
DoubleBufferedCanvas() {
}
public void update(Graphics g) {
paint(g);
}
public Graphics startPaint(Graphics sysgraph) {
mSystemGraphics = sysgraph;
Dimension d = getSize();
if ((mActiveOffscreenImage == null) ||
(d.width != mOffscreenSize.width) ||
(d.height != mOffscreenSize.height)) {
mActiveOffscreenImage = createImage(d.width, d.height);
mActiveOffscreenGraphics = mActiveOffscreenImage.getGraphics();
mOffscreenSize = d;
mActiveOffscreenGraphics.setFont(getFont());
}
return mActiveOffscreenGraphics;
}
public void endPaint() {
mSystemGraphics.drawImage(mActiveOffscreenImage, 0, 0, null);
}
}
}
提琴曲。java
import java.awt.*;
private boolean squares[][];
private int type;
private Point position = new Point(3, -4); // -4 to start above top row
public int getX() { return position.x; }
public int getY() { return position.y; }
public void setX(int newx) { position.x = newx; }
public void setY(int newy) { position.y = newy; }
public void setPosition(int newx, int newy) { setX(newx); setY(newy);
}
public TetrisPiece(int type) {
this.type = type;
this.squares = new boolean[4][4];
for(int i=0; i<4; i++)
for(int j=0; j<4; j++)
this.squares[i][j] = Tetris.PIECE_BITS[type][i][j];
}
public boolean canStepDown() {
synchronized(Tetris.timer) {
cut();
position.y++;
boolean OK = canPaste();
position.y--;
paste();
return OK;
}
}
public boolean canPaste() {
for(int i=0; i<4; i++) {
for(int j=0; j<4; j++) {
int to_x = j + position.x;
int to_y = i + position.y;
if(squares[i][j]) {
//checks if sqaure is too far left or right
if(0 > to_x || to_x >= Tetris.COLUMNS
|| to_y >= Tetris.ROWS) // square off bottom?
{
return false;
// This allows the user to move a piece before it drops
// completely into view.
}
if(to_y >= 0 && Tetris.grid[to_y][to_x] != Tetris.EMPTY)
return false;
}
}
}
return true;
}
public void stepDown() {
position.y++;
}
public void cut() {
for(int i=0; i<4; i++)
for(int j=0; j<4; j++)
if(squares[i][j] && position.y+i>=0)
Tetris.grid[position.y + i][position.x + j] = Tetris.EMPTY;
}
/**
* Paste the color info of this piece into the given grid
*/
public void paste(int into[][]) {
for(int i=0; i<4; i++)
for(int j=0; j<4; j++)
if(squares[i][j] && position.y+i>=0)
into[position.y + i][position.x + j] = type;
}
/**
* No argument version assumes pasting into main game grid
*/
public void paste() {
paste(Tetris.grid);
}
// this method is a bit of a hack to check for the case
// where a piece may be safely on the grid but have one or more
// rows of empty squares that are above the grid and therefore OK
public boolean isTotallyOnGrid() {
for(int i=0; i<4; i++) {
if(position.y + i >= 0)
return true; //everything from here down is on grid
// this row is above grid so look for non-empty squares
for(int j=0; j<4; j++)
if(squares[i][j])
return false;
}
System.err.println("TetrisPiece.isTotallyOnGrid internal error");
return false;
}
}
TetrisMain。java
import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
public class TetrisMain {
public static void main(String[] args) {
Frame frame = new Frame("Tetris");
Tetris tetris = new Tetris();
frame.add(tetris);
tetris.init();
tetris.start();
tetris.startGame();
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
frame.setSize(250,500);
frame.setResizable(false);
frame.setVisible(true);
}
}
# 1 楼答案
我猜您正试图从
Tetris类在IDE中运行，这就是它在那里寻找main()（程序的“入口点”）方法的原因。i、 e您已将
main()方法移动到TetrisMain，因此需要从那里运行它