piece.java

一些JAVA的小程序

//
//	tetris game
//	written by Tim Budd, January 1997
//

import java.awt.*;

class Piece {
		// data fields
	private int x[];
	private int y[];
	private Color color;
		// moves
	public static final int Down = 1;
	public static final int Left = 2;
	public static final int Rotate = 3;
	public static final int Right = 4;
	
		// constructor
	public Piece (int type) 
	{
		switch(type) {
			case 1:	// 
				x = new int[4];
				y = new int[4];
				x[0] = 7;
				y[0] = 29;
				x[1] = 7;
				y[1] = 28;
				x[2] = 8;
				y[2] = 28;
				x[3] = 8;
				y[3] = 27;
				color = Color.green;
				break;
			case 2:	// 
				x = new int[4];
				y = new int[4];
				x[0] = 7;
				y[0] = 29;
				x[1] = 8;
				y[1] = 29;
				x[2] = 8;
				y[2] = 28;
				x[3] = 9;
				y[3] = 28;
				color = Color.blue;
				break;
			case 3:	// 
				x = new int[4];
				y = new int[4];
				x[0] = 7;
				y[0] = 29;
				x[1] = 7;
				y[1] = 28;
				x[2] = 8;
				y[2] = 28;
				x[3] = 9;
				y[3] = 28;
				color = Color.red;
				break;
			case 4:	// 
				x = new int[4];
				y = new int[4];
				x[0] = 7;
				y[0] = 28;
				x[1] = 8;
				y[1] = 28;
				x[2] = 9;
				y[2] = 28;
				x[3] = 9;
				y[3] = 29;
				color = Color.yellow;
				break;
			case 5:	// 
				x = new int[4];
				y = new int[4];
				x[0] = 7;
				y[0] = 29;
				x[1] = 8;
				y[1] = 29;
				x[2] = 7;
				y[2] = 28;
				x[3] = 8;
				y[3] = 28;
				color = Color.orange;
				break;
			case 6:	// 
				x = new int[5];
				y = new int[5];
				x[0] = 6;
				y[0] = 29;
				x[1] = 7;
				y[1] = 29;
				x[2] = 8;
				y[2] = 29;
				x[3] = 9;
				y[3] = 29;
				x[4] = 10;
				y[4] = 29;
				color = Color.green;
				break;
			case 7:	// 
				x = new int[4];
				y = new int[4];
				x[0] = 7;
				y[0] = 28;
				x[1] = 8;
				y[1] = 28;
				x[2] = 9;
				y[2] = 28;
				x[3] = 8;
				y[3] = 29;
				color = Color.green;
				break;
			default:
				System.out.println("Tried to create object value " + type);

			}
	}
	
	private void erase (Color [][] table)
	{
		for (int i = 0; i < x.length; i++)
			table[x[i]][y[i]] = Color.white;
	}
	
	private void draw (Color [][] table)
	{
		for (int i = 0; i < x.length; i++)
			table[x[i]][y[i]] = color;
	}
	
	private boolean testPosition (int x, int y, Color[][] table)
	{
		if ((x < 0) || (x > 14))
			return false;
		if ((y < 0) || (y > 29))
			return false;
		if (table[x][y] != Color.white)
			return false;
		return true;
	}
	
	private boolean testDown (Color [][] table)
	{
		for (int i = 0; i < x.length; i++)
			if (! testPosition(x[i], y[i]-1, table))
				return false;
		return true;
	}
	
	private boolean testMoveRight (Color [][] table)
	{
		for (int i = 0; i < x.length; i++)
			if (! testPosition(x[i]+1, y[i], table))
				return false;
		return true;
	}
	
	private boolean testMoveLeft (Color [][] table)
	{
		for (int i = 0; i < x.length; i++)
			if (! testPosition(x[i]-1, y[i], table))
				return false;
		return true;
	}
		
	private boolean testRotate (Color [][] table)
	{
		for (int i = 0; i < x.length; i++) {
			int dx = x[i] - x[1];
			int dy = y[i] - y[1];
			int nx = x[1] + dy;
			int ny = y[1] - dx;
			if (! testPosition(nx, ny, table))
				return false;
			}
		return true;
	}
		
	private void moveDown ()
	{
		for (int i = 0; i < x.length; i++)
			y[i] = y[i] - 1;
	}
	
	private void moveRight ()
	{
		for (int i = 0; i < x.length; i++)
			x[i] = x[i] + 1;
	}
	
	private void moveLeft ()
	{
		for (int i = 0; i < x.length; i++)
			x[i] = x[i] - 1;
	}	
	
	private void moveRotate ()
	{
		for (int i = 0; i < x.length; i++) {
			int dx = x[i] - x[1];
			int dy = y[i] - y[1];
			x[i] = x[1] + dy;
			y[i] = y[1] - dx;
			}
	}
		
	public boolean move (int command, Color [][] table) {
		erase(table);
		boolean canDoIt = false;
		switch (command) {
			case Down: canDoIt = testDown(table); break;
			case Right: canDoIt = testMoveRight(table); break;
			case Left: canDoIt = testMoveLeft(table); break;
			case Rotate: canDoIt = testRotate(table); break;
			}
		if (canDoIt)
			switch (command) {
				case Down: moveDown(); break;
				case Right: moveRight(); break;
				case Left: moveLeft(); break;
				case Rotate: moveRotate(); break;
				}
		draw(table);
		if (command == Down)
			return canDoIt;
		return true;
		}	
}