seqstack.java

来自「基本数据结构」· Java 代码 · 共 42 行

package seqStack;

public class SeqStack implements Stack
{
	final int defaultSize=10;
	int top;
	Object[] stack;
	int maxStackSize;
	private void initiate(int sz)
	{
		maxStackSize=sz;
		top=0;
		stack=new Object[maxStackSize];
	}
	public SeqStack(){initiate(defaultSize);}
	public SeqStack(int sz){initiate(sz);}
	public class FullStackException extends RuntimeException{

		/**
		 * 
		 */
		private static final long serialVersionUID = 3384799606707801851L;}
	public void push(Object obj) 
	{
		if(top==maxStackSize)throw new FullStackException();
		stack[top]=obj;
		top++;
	}
	public Object pop()
	{
		if(top==0)throw new java.util.EmptyStackException();
		top--;
		return stack[top];
	}
	public Object getTop()
	{
		if(top==0)throw new java.util.EmptyStackException();
		return stack[top-1];
	}
	public boolean notEmpty(){return (top>0);}
}