数据结构代码-简单链表

/**
 * 简单链表节点
 */
package linklist;

/**
 * 
 */
public class Link {
	int iData;
	double dData;
	public Link next;

	public Link(int iData, double dData) {
		this.iData = iData;
		this.dData = dData;
		next = null;
	}

	public void displayLink() {
		System.out.println("{" + iData + "," + dData + "}");
	}
}

/**
 * 简单链表数据结构
 */
package linklist;

/**
 * 
 */
public class LinkList
{
    private Link first;
    
    public LinkList()
    {
        first = null;
    }
    
    /**
     * 判断链表是否为空
     * 
     * @return
     */
    public boolean isEmpty()
    {
        return first == null;
    }
    
    /**
     * 在链表头部插入元素
     * 
     * @param iData
     * @param dData
     */
    public void insertFirst(int iData, double dData)
    {
        Link link = new Link(iData, dData);
        link.next = first;
        first = link;
    }
    
    /**
     * 在链表头部删除元素
     * 
     * @return
     * @throws EmptyLinkListException
     */
    public Link deleteFirst()
        throws EmptyLinkListException
    {
        if (isEmpty())
        {
            throw new EmptyLinkListException();
        }
        else
        {
            Link temp = first;
            first = first.next;
            return temp;
        }
    }
    
    /**
     * 查找指定关键字的节点
     * 
     * @param key
     * @return
     */
    public Link find(int key)
    {
        Link current = first;
        while (current != null)
        {
            if (key == current.iData)
            {
                break;
            }
            else
            {
                current = current.next;
            }
        }
        return current;
    }
    
    /**
     * 删除指定关键字的节点
     * 
     * @param key
     * @return
     * @throws EmptyLinkListException
     */
    public Link delete(int key)
        throws EmptyLinkListException
    {
        if (isEmpty())
        {
            throw new EmptyLinkListException();
        }
        else if (first.iData == key)
        {// 要找的元素在首节点
            return deleteFirst();
        }
        else
        {
            Link current = first.next;
            Link previous = first;
            while (current != null)
            {
                if (current.iData == key)
                {
                    previous.next = current.next;
                    break;
                }
                previous = current;
                current = current.next;
            }
            return current;
        }
    }
    
    /**
     * 按照整型key升序插入元素,规则为大于前一个元素，小于或者等于后一个元素
     * @see [类、类#方法、类#成员]
     */
    public void insertByAscend(int iData, double dData)
    {
        Link link = new Link(iData, dData);
        //如果链表为空，或键值比表头还小也做表头
        if (isEmpty() || iData <= first.iData)
        {
            link.next = first;
            first = link;
        }
        else
        {
            Link current = first;
            Link next = current.next;
            while (iData > current.iData)
            {
                if (next == null || iData <= next.iData)
                {
                    link.next = current.next;
                    current.next = link;
                    break;
                }
                current = next;
                next = current.next;
            }
        }
    }
    
    /**
     * 遍历链表
     */
    public void displayList()
    {
        Link current = first;
        while (current != null)
        {
            current.displayLink();
            current = current.next;
        }
    }
    
    /**
     * 返回首元素
     * @return
     * @see [类、类#方法、类#成员]
     */
    public Link getFirst()
    {
        return first;
    }
}

/**
 * 简单链表测试类
 */
package linklist;


/**
 * 
 */
public class LinkListTest {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		LinkList linkList = new LinkList();
		linkList.insertFirst(1, 1.1);
		linkList.insertFirst(2, 2.2);
		linkList.insertFirst(3, 3.3);
		try {
			linkList.delete(3);
			linkList.displayList();
		} catch (EmptyLinkListException e) {
			e.printStackTrace();
		}
	}

}