· URL下载资源

public class Url {
    public static void main(String[] args) throws Exception {
        URL url =  new URL("http://localhost:8081/qinjiang/hanbin.txt");
        HttpURLConnection urlConnection = (HttpURLConnection)url.openConnection();

        InputStream inputStream = urlConnection.getInputStream();

        FileOutputStream fos = new FileOutputStream("hanbin.txt");
        byte[] buffer = new byte[1024];
        int len;
        while((len = inputStream.read(buffer))!=-1){
            fos.write(buffer,0,len);//写出这个资源
        }
        fos.close();
        inputStream.close();
        urlConnection.disconnect();
    }
}

首先先开启Tomcat才行