我有这段代码:publicstaticvoidmain(String[]args){Downoaderdown=newDownoader();Downoaderdown2=newDownoader();down.downloadFromConstructedUrl("http:xxxxx",newFile("./references/word.txt"),newFile("./references/words.txt"));down2.downloadFromConstructedUrl("http:xxxx",newFile("./references/word1.txt"),new