JAVA技巧:用鏈表實現(xiàn)棧

實現(xiàn)代碼如下：
    interface StackPK{
    void Push(Object obj);
    Object Pop();
    boolean isEmpty();
    int Size();
    }
    public class LinkStack implements StackPK{
    private class SLLNode{
    private Object data;
    private SLLNode next;
    SLLNode(){}
    SLLNode(Object obj){
    data=obj;
    }
    public void setData(Object o){
    if(o==null)
    throw new IllegalArgumentException("object is null");
    data=o;
    }
    public Object getData(){
    return data;
    }
    public void setNext(SLLNode n){
    next=n;
    }
    public SLLNode getNext(){
    return next;
    }
    public String toString(){
    return (String)data;
    }
    }
    private SLLNode top;
    public LinkStack(){
    top=null;
    }
    public void Push(Object obj){
    if(obj==null)
    throw new IllegalArgumentException("n is null");
    if(top==null)
    {
    SLLNode temp=new SLLNode(obj);
    top=temp;
    }
    else
    {
    SLLNode temp=new SLLNode(obj);
    temp.setNext(top);
    top=temp;
    }
    }
    public Object Pop(){
    SLLNode temp;
    if(top==null)
    throw new IllegalArgumentException("stack is empty");
    temp=top;
    top=top.getNext();
    return temp.getData();
    }
    public boolean isEmpty(){
    if(top == null)
    return true;
    else
    return false;
    }
    public int Size(){
    SLLNode cnt;
    cnt=top;
    int count=0;
    if(cnt == null)
    return 0;
    while(cnt != null){
    ++count;
    cnt=cnt.getNext();
    }
    return count;
    }
    public static void main(String[] args){
    LinkStack ls=new LinkStack();
    Object[] arr=new String[]{"liangming","gaojie","liangbing","wuxia","zhangjun"};
    for(int i=0;i　　ls.Push(arr[i]);
    while(ls.Size()>0)
    {
    System.out.println(ls.Pop());
    }
    }
    }