wagon.java

一个基于Java的小游戏

import java.awt.*;

public class Wagon {

	// Constants to represent the direction of the Wagon
	private final int LEFT =  0;
	private final int RIGHT = 1;
	private final int UP =    2;
	private final int DOWN =  3;

	// The size of the wagon
	private final int SIZE = 8;

	private int xPos, yPos;
	private int direction;

	//The speed of the wagon
	private final int SPEED = 5;

	public Wagon(int x, int y) {
		xPos = x;
		yPos = y;
		direction = UP;
	}

	//To change the facing direction of the wagon.
	public void faceUp(){
		direction = UP;
	}
	public void faceDown(){
		direction = DOWN;
	}
	public void faceLeft(){
		direction = LEFT;
	}
	public void faceRight(){
		direction = RIGHT;
	}

	//To move the wagon
	public void move(Rectangle boundary){
		if(direction == UP && yPos - SIZE > boundary.y){
			yPos -= SPEED;
		}else if(direction == DOWN && yPos + SIZE  < boundary.y + boundary.height){
			yPos += SPEED;
		}else if(direction == LEFT && xPos - SIZE  > boundary.x){
			xPos -= SPEED;
		}else if(direction == RIGHT && xPos + SIZE  < boundary.x + boundary.width){
			xPos += SPEED;
		}
	}

	//Pass the current position of the wagon
	public int getX(){
		return xPos - SIZE;
	}
	public int getY(){
		return yPos - SIZE;
	}
	public int getSize(){
		return SIZE;
	}


	// Display the wagon.  The direction the wagon is facing
	// is indicated by a narrow rectangle.
	public void draw(Graphics g) {

		// Draw the main body of the wagon
		g.setColor(Color.blue);
		g.fillRect(xPos-SIZE, yPos-SIZE, 2*SIZE, 2*SIZE);
		g.setColor(Color.black);
		g.drawRect(xPos-SIZE, yPos-SIZE, 2*SIZE, 2*SIZE);

		// Calculate the position of the direction indicator
		Rectangle directionIndicator;
		if (direction == UP) {
			directionIndicator = new Rectangle(xPos-SIZE+2, yPos-SIZE+2, 2*SIZE-4, 3);
		} else if (direction == DOWN) {
			directionIndicator = new Rectangle(xPos-SIZE+2, yPos+SIZE-5, 2*SIZE-4, 3);
		} else if (direction == LEFT) {
			directionIndicator = new Rectangle(xPos-SIZE+2, yPos-SIZE+2, 3, 2*SIZE-4);
		} else {
			directionIndicator = new Rectangle(xPos+SIZE-5, yPos-SIZE+2, 3, 2*SIZE-4);
		}

		// Draw the direction indicator
		g.setColor(Color.white);
		g.fillRect(directionIndicator.x, directionIndicator.y, directionIndicator.width, directionIndicator.height);
		g.setColor(Color.black);
		g.drawRect(directionIndicator.x, directionIndicator.y, directionIndicator.width, directionIndicator.height);
	}

}