linkedbag.java

用数组实现的bingo游戏程序

/**
 * 
 */
package jss.bag;

import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Random;

/**
 * @author Sean.N.Zhang
 * 
 */
public class LinkedBag implements BagADT {
	public void add(Object element) {
		LinearNode node = new LinearNode(element);
		node.setNext(contents);
		contents = node;
		count++;
	}

	public void addAll(BagADT bag) {
		// TODO Auto-generated method stub

	}

	public boolean contains(Object target) {
		// TODO Auto-generated method stub
		return false;
	}

	public boolean equals(BagADT bag) {
		// TODO Auto-generated method stub
		return false;
	}

	public boolean isEmpty() {
		// TODO Auto-generated method stub
		return false;
	}

	public Iterator iterator() {
		return new LinkedIterator(contents,count);
	}

	public Object remove(Object target) {
		boolean found = false;
		LinearNode previous, current;
		Object result = null;
		if (contents.getElement().equals(target)) {
			result = contents.getElement();
			contents = contents.getNext();
		} else {
			previous = contents;
			current = contents.getNext();
			for (int look = 1; look < count && !found; look++)
				if (current.getElement().equals(target))
					found = true;
				else {
					previous = current;
					current = current.getNext();
				}
			if (!found)
				throw new NoSuchElementException();

			result = current.getElement();
			previous.setNext(current.getNext());
		}
		count--;
		return result;
	}

	public Object removeRandom() {
		LinearNode previous, current;
		Object result = null;
		int pick = rand.nextInt(count) + 1;

		if (pick == 1) {
			result = contents.getElement();
			contents = contents.getNext();
		} else {
			previous = contents;
			for (int skip = 2; skip < pick; skip++)
				previous = previous.getNext();
			current = previous.getNext();
			result = current.getElement();
			previous.setNext(current.getNext());
		}
		count--;
		return result;
	}

	public int size() {
		// TODO Auto-generated method stub
		return 0;
	}

	public BagADT union(BagADT set) {
		// TODO Auto-generated method stub
		return null;
	}

	private static Random rand = new Random();

	private int count;

	private LinearNode contents;

	public static Random getRand() {
		return rand;
	}

	public static void setRand(Random rand) {
		LinkedBag.rand = rand;
	}

	public LinearNode getContents() {
		return contents;
	}

	public void setContents(LinearNode contents) {
		this.contents = contents;
	}

	public int getCount() {
		return count;
	}

	public void setCount(int count) {
		this.count = count;
	}
}