主类
package DataStructures;
public
class LinkedStack
{
private ListNode topOfStack;
public LinkedStack() { topOfStack = null;
} public boolean IsFull() { return false; } public boolean IsEmpty() { return topOfStack == null; } public void makeEmpty() { topOfStack = null; } /** * Insert a new item into the stack. * * @param x * the item to insert. */ public void Push(Object x) { topOfStack = new ListNode(x, topOfStack); } /** * Get the most recently inserted item in the stack. Does not alter the * stack * * @return the most recently inserted item in the stack, or null if empty */ public Object Top() { if (IsEmpty()) return null; return topOfStack.element; } /** * Remove the most recenly inserted item from the stack. * * @throws Underflow */ public void Pop() throws Underflow { if (IsEmpty()) throw new Underflow(); topOfStack = topOfStack.next; } /** * Return and remove the most recently inserted item from the stack. * * @return the most recently iserted item in the stack, or null if empty. */ public Object TopAndPop() { if (IsEmpty()) return null; Object topItem = topOfStack.element; topOfStack = topOfStack.next; return topItem; }
}
异常类
package DataStructures;
/** * Exception class for access in empty containers such as stacks, queues, and * priority queues. */
public
class Underflow
extends Exception
{}
本文转自冬冬博客园博客，原文链接：http://www.cnblogs.com/yuandong/archive/2006/08/23/484554.html
，如需转载请自行联系原作者
