JAVA实现栈

package linklist;/** * JAVA实现栈的数据结构(先进后出) * 使用数组的形式来存储 * @author zhang * */public class Stack {    private Object[] stackElement;    private int length = 16;    private int size = 0;    private int postion = 0;   //游标位置    public Stack(){}    public Stack(int length){        this.length = length;    }    /**     * 判断是不是已经满了     * @return     */    private boolean isFul(){        if(postion == size){            return true;        }else{            return false;        }    }    /**     * 如果装满了，则申请新的空间，把原来的空间上的复制到新的空间     */    private void copy(){        Object ele[] = new Object[length+16];  //每次扩增16        for(int i=0;i<stackElement.length;i++){            ele[i] = stackElement[i];  //复制        }        this.length = length+16;        stackElement = ele;    }    /**     * 进栈     * @param element     */    public void push(Object element){        if(stackElement == null){            stackElement = new Object[length];            stackElement[postion] = element;            postion++;        }else{            if(isFul() == true){                copy();     //创建新的空间，增加存储区域                stackElement[postion] = element;                postion++;            } else {                stackElement[postion] = element;                postion++;            }        }    }    /**     * 出栈     * @return     */    public Object pop(int pos){        if(stackElement != null && pos>=0 && pos<=postion){            return stackElement[pos];        }        return null;    }    /**     * 遍历所有     */    public void display(){        for(int i=postion;i>0;i--){            Object obj = pop(i);            System.out.println(obj.toString());        }    }    public static void main(String[] args) {        Stack stack = new Stack();        for(int i=0;i<10;i++){            stack.push(i);        }        stack.display();    }}