downloadutil.java

多线程下载器。该小程序模范迅雷等下载器的下载原理实现多线程下载

package com;

/**
 * <p>Title: </p>
 *
 * <p>Description: </p>
 *
 * <p>Copyright: Copyright (c) 2009</p>
 *
 * <p>Company: </p>
 *
 * @author not attributable
 * @version 1.0
 */

import java.net.HttpURLConnection;
import java.net.URL;

public class DownloadUtil {

        public int getFileLength(String url) throws Exception{
                int length = 0;
                URL downladURL = new URL(url);
                HttpURLConnection con = (HttpURLConnection) downladURL.openConnection();

                int stateCode = con.getResponseCode();
                if (stateCode != 200) {
                        length =  -1;
                }

                int size = con.getContentLength();
                con.disconnect();
                length = size;
                return length;
        }

        public boolean isFinished(boolean[] isStop){
                boolean isFinished = false;
                for(int i=0;i<isStop.length;){
                        boolean flag = isStop[i];
                        if(!flag){
                                try{
                                        Thread.sleep(3000);
                                }catch(Exception e){
                                        e.printStackTrace();
                                }
                                isFinished = false;
                        }else{
                                isFinished = true;
                                i++;
                        }
                }
                return true;
        }

}