list.java

模拟操作系统的存储过程

import java.awt.*;
import java.awt.event.*;


class ListNode {
    int data;
    ListNode next;

    ListNode( int idata , ListNode nextNode )
    {
       data = idata;
       next = nextNode;
      
    }
}      
public class List {
	private ListNode head;  //记录链表头
	private ListNode tail;  //记录链表尾
	private String name;
	private int size;
	
	public List( String s ) //构造函数初始化一链表
	{
		name = s;
		head = tail = null;
		size = 0;
	}
	
	public List() //构造函数初始化一链表
	{
		this( "List" );
	}
	
    public void insertAtFront( int insertItem ) //在链表头部插入节点
    {
    	if ( isEmpty() )
           head = tail = new ListNode( insertItem , null );
        else
           head = new 	ListNode( insertItem ,head );
        size++;
              
     }
     
    public void insertAtBack ( int insertItem ) //在链表尾部插入
    {
    	if ( isEmpty() )
           head = tail = new ListNode( insertItem , null );
        else
           tail = tail.next = new ListNode( insertItem ,null );
        size++;
           
    }
    
    public int removeFromFront() //删除链表头部节点，并返回结点数据
    {
    	int removeItem = 0;
    	
           removeItem = head.data;
         
        if ( head.equals(tail) )    	
           head = tail = null;
        else
           head = head.next;
        size--;   
        return removeItem;
        
     }
     
     
     public int remove ( int item ) //删除链表中第一个结点数据等于参数的那个结点
     {
     	int removeItem = 0;
     	if( head.equals(tail ) )
     	   head = tail = null;
     	else{
     		ListNode current = head;
     		while (current.data != item )
     	     	current = current.next;
     	     	removeItem = current.data;
     	     }
     	size--;    
     	     	
     	return removeItem;
     	      
     }
     
    public boolean lrucompare( int k ) // 比较在链表中结点中数据是否有与参数相等的，又返回true
    {
    	ListNode temp = new ListNode( 0 , null );
    	temp = head;
    	while( temp != tail )
    	 {
    	 	if( temp.data == k )
    	    return true;
    	    temp = temp.next; 
    	 } 
    	 return false; 
    }
    
    public ListNode lrureplace( int k ) //返回比较在链表中结点中数据与参数相等的结点位置
    {
     	ListNode temp = new ListNode( 0 , null );
    	temp = head;
    	while( temp != tail )
    	 {
    	 	if( temp.data == k )
    	    return temp;
    	    temp = temp.next; 
    	 } 
    	 return null;    	
    }
    
        
     
     public boolean isEmpty() //判断是链表是否为空
     { return head == null;}
     
     public int getSize(){ return this.size;}
}