这一项工作：
public class Download { private static boolean isRedirected( Map<String, List<String>> header ) { for( String hv : header.get( null )) { if( hv.contains( " 301 " ) || hv.contains( " 302 " )) return true; } return false; } public static void main( String[] args ) throws Throwable { String link = "http://github.com/downloads/TheHolyWaffle/ChampionHelper/" + "ChampionHelper-4.jar"; String fileName = "ChampionHelper-4.jar"; URL url = new URL( link ); HttpURLConnection http = (HttpURLConnection)url.openConnection(); Map< String, List< String >> header = http.getHeaderFields(); while( isRedirected( header )) { link = header.get( "Location" ).get( 0 ); url = new URL( link ); http = (HttpURLConnection)url.openConnection(); header = http.getHeaderFields(); } InputStream input = http.getInputStream(); byte[] buffer = new byte[4096]; int n = -1; OutputStream output = new FileOutputStream( new File( fileName )); while ((n = input.read(buffer)) != -1) { output.write( buffer, 0, n ); } output.close(); }}
