URL url = null;

       URLConnection urlCon;

       InputStream inStream;// 你只需判断这个变量值 .

       try {

        url = new URL(

          "");

        urlCon = url.openConnection();

        inStream = urlCon.getInputStream();

        if (inStream != null) {

         System.out.println(host+"中有xml文件，且tomcat已启动");

        } 

       } catch (java.net.ConnectException e) {

        System.out.println(host+"tomcat没有启动");

       }

     

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