messagequeue.java

GPRS数据通讯软件源码

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 * 消息列队实现
 * 其中元素均为byte[]
 */

package documenteditor;

import java.util.Vector;

/**
 *
 * @author wangzhi
 */
public class MessageQueue extends Vector{
    
    private int Len = 0;//列队长度，超过则从头部删掉元素
    
    public MessageQueue(int Len){
        this.Len = Len;
    }

    //进列队，返回元素个数
    public int Enqueue(byte[] buff) {
        super.add(buff);
        int count = super.size();
        if(count>Len){
            super.remove(0);
        }
        return super.size();
    }
    
    //以字符串形式进列队，返回元素个数
    public int Enqueue(String Message){
        super.add(Message.getBytes());
        int count = super.size();
        if(count>Len){
            super.remove(0);
        }
        return super.size();
    }
    
    //以字符串形势出列队
    public String Dequeue(){
        if(this.size()>0){
            byte[] RStr = (byte[])this.get(0);            
            super.remove(0);
            return new String(RStr);            
        }else{
            return null;
        }            
    }
    
    //出列队
    public byte[] DequeueByte(){
        if(this.size()>0){
            byte[] RStr = (byte[])this.get(0);
            super.remove(0);
            return RStr;            
        }else{
            return null;
        }            
    }

}