用Java实现HTTP文件队列下载

　　上面的示例代码就将网络资源的内容保存到了本地指定的文件中。

　　5.代码清单

importjava.io.*;importjava.net.*;importjava.util.*;/***<p>Title:个人开发的API</p>*<p>Description:将指定的HTTP网络资源在本地以文件形式存放</p>*<p>Copyright:Copyright(c)2004</p>*<p>Company:NewSky</p>*@authorMagicLiao*@version1.0*/publicclassHttpGet{publicfinalstaticbooleanDEBUG=true;//调试用privatestaticintBUFFER_SIZE=8096;//缓冲区大小privateVectorvDownLoad=newVector();//URL列表privateVectorvFileList=newVector();//下载后的保存文件名列表/***构造方法*/publicHttpGet(){}/***清除下载列表*/publicvoidresetList(){vDownLoad.clear();vFileList.clear();}/***增加下载列表项**@paramurlString*@paramfilenameString*/publicvoidaddItem(Stringurl,Stringfilename){vDownLoad.add(url);vFileList.add(filename);}/***根据列表下载资源*/publicvoiddownLoadByList(){Stringurl=null;Stringfilename=null;//按列表顺序保存资源for(inti=0;i<vDownLoad.size();i++){url=(String)vDownLoad.get(i);filename=(String)vFileList.get(i);try{saveToFile(url,filename);}catch(IOExceptionerr){if(DEBUG){System.out.println("资源["+url+"]下载失败!!!");}}}if(DEBUG){System.out.println("下载完成!!!");}}/***将HTTP资源另存为文件**@paramdestUrlString*@paramfileNameString*@throwsException*/publicvoidsaveToFile(StringdestUrl,StringfileName)throwsIOException{FileOutputStreamfos=null;BufferedInputStreambis=null;HttpURLConnectionhttpUrl=null;URLurl=null;byte[]buf=newbyte[BUFFER_SIZE];intsize=0;//建立链接url=newURL(destUrl);httpUrl=(HttpURLConnection)url.openConnection();//连接指定的资源httpUrl.connect();//获取网络输入流bis=newBufferedInputStream(httpUrl.getInputStream());//建立文件fos=newFileOutputStream(fileName);if(this.DEBUG)System.out.println("正在获取链接["+destUrl+"]的内容...\n将其保存为文件["+fileName+"]");//保存文件while((size=bis.read(buf))!=-1)fos.write(buf,0,size);fos.close();bis.close();httpUrl.disconnect();}/***设置代理服务器**@paramproxyString*@paramproxyPortString*/publicvoidsetProxyServer(Stringproxy,StringproxyPort){//设置代理服务器System.getProperties().put("proxySet","true");System.getProperties().put("proxyHost",proxy);System.getProperties().put("proxyPort",proxyPort);}/***设置认证用户名与密码**@paramuidString*@parampwdString*/publicvoidsetAuthenticator(Stringuid,Stringpwd){Authenticator.setDefault(newMyAuthenticator(uid,pwd));}/***主方法(用于测试)**@paramargvString[]*/publicstaticvoidmain(Stringargv[]){HttpGetoInstance=newHttpGet();try{//增加下载列表（此处用户可以写入自己代码来增加下载列表）oInstance.addItem("http://www.ebook.com/java/网络编程001.zip","./网络编程1.zip");oInstance.addItem("http://www.ebook.com/java/网络编程002.zip","./网络编程2.zip");oInstance.addItem("http://www.ebook.com/java/网络编程003.zip","./网络编程3.zip");oInstance.addItem("http://www.ebook.com/java/网络编程004.zip","./网络编程4.zip");oInstance.addItem("http://www.ebook.com/java/网络编程005.zip","./网络编程5.zip");oInstance.addItem("http://www.ebook.com/java/网络编程006.zip","./网络编程6.zip");oInstance.addItem("http://www.ebook.com/java/网络编程007.zip","./网络编程7.zip");//开始下载oInstance.downLoadByList();}catch(Exceptionerr){System.out.println(err.getMessage());}}}