一个简单的数字彩票游戏类

[java]代码库

import java.util.Arrays;

/**
 * NumberLotteryGame 一个简单的数字彩票游戏类
 * 
 * @author LuisZhang 参考了core java 8th中的例3-7的设计思想
 */
public class NumberLotteryGame {
	private int gamesNumber; // 生成游戏的数量，为以后多线程扩展做考虑
	private int numbersLength; // 数字序列的总长度
	private int winningNumbersLength; // 中奖的数字序列的长度

	/**
	 * Constructor with three parameters 初始化3个参数的构造方法
	 * 
	 * @param gamesNumber
	 * @param numbersLength
	 * @param winningNumbersLength
	 */
	public NumberLotteryGame(int gamesNumber, int numbersLength,
			int winningNumbersLength) {
		this.gamesNumber = gamesNumber;
		this.numbersLength = numbersLength;
		this.winningNumbersLength = winningNumbersLength;
	}

	/**
	 * Generate a number Array 生成一个产生中奖序列所需的数字序列
	 * 
	 * @param length
	 *            数字序列的长度
	 * @return numbers 产生的数字序列
	 */
	public static int[] generateNumberArray(int length) {
		int[] numbers = new int[length];

		for (int i = 0; i < numbers.length; i++) {
			numbers[i] = i + 1;
		}

		return numbers;
	}

	/**
	 * Generate a winning number array 根据生成的数字序列，产生不重复的中奖数字序列
	 * 
	 * @param length
	 *            中奖数字序列的长度
	 * @return result 中奖数字数组
	 */
	public int[] generateWinningNumberArray(int length) {
		int[] numbers = NumberLotteryGame.generateNumberArray(numbersLength);

		int[] result = new int[length];

		int n = numbersLength;

		// 该for循环为产生不重复的中奖序列的核心代码
		for (int i = 0; i < result.length; i++) {
			int r = (int) (Math.random() * n); // 随机产生一个从0——(n-1)的数字,Math.random()
			// 随机产生一个[0, 1)范围的double型数值,
			result[i] = numbers[r]; // 将该随机数字作为数组的下标，
									// 将该下标对应的值赋给result[i]
			numbers[r] = numbers[n - 1]; // 将numbers数组的numbers[n-1]的值，赋给刚已赋
											// 值过的numbers[r]。
			n--; // 将n-1,从而下一次循环产生的随机的原数组下标的范围从0——（n-1）-1,
					// 保证了上一步中，已经赋值给数组中其他数的numbers[n-1]，不会在下次循环中给取
					// 得，从而保证了产生的中奖数组result为不重复的。
		}

		return result;
	}

	/**
	 * Show winning NumberArray 显示中将数组
	 */
	public void showWinningNumberArray() {
		int[] winningNumbers = this
				.generateWinningNumberArray(winningNumbersLength);
		Arrays.sort(winningNumbers);

		for (int r : winningNumbers) {
			System.out.print(r + " ");
		}

		System.out.println();
	}

	/**
	 * @return the gamesNumber
	 */
	public int getGamesNumber() {
		return gamesNumber;
	}

	/**
	 * @param gamesNumber
	 *            the gamesNumber to set
	 */
	public void setGamesNumber(int gamesNumber) {
		this.gamesNumber = gamesNumber;
	}

	/**
	 * @return the numbersLength
	 */
	public int getNumbersLength() {
		return numbersLength;
	}

	/**
	 * @param numbersLength
	 *            the numbersLength to set
	 */
	public void setNumbersLength(int numbersLength) {
		this.numbersLength = numbersLength;
	}

	/**
	 * @return the winningNumbersLength
	 */
	public int getWinningNumbersLength() {
		return winningNumbersLength;
	}

	/**
	 * @param winningNumbersLength
	 *            the winningNumbersLength to set
	 */
	public void setWinningNumbersLength(int winningNumbersLength) {
		this.winningNumbersLength = winningNumbersLength;
	}

	/**
	 * Main method 用于测试该类的main方法
	 * 
	 * @param args
	 */
	public static void main(String[] args) {
		int i = 20; // int i = Integer.parseInt(args[0]);
		for (int j = 0; j < i; j++) {
			NumberLotteryGame game1 = new NumberLotteryGame(1, 15, 7);
			game1.showWinningNumberArray();
		}
	}
}