JarURLConnection.getMainAttributes() has the following syntax.
public Attributes getMainAttributes() throws IOException
In the following code shows how to use JarURLConnection.getMainAttributes() method.
import java.net.JarURLConnection; import java.net.URL; import java.util.jar.Attributes; //from w ww. j a v a2 s. c om public class Main { public static void main(String[] argv) throws Exception { URL url = new URL("jar:file:/c://my.jar!/"); JarURLConnection conn = (JarURLConnection) url.openConnection(); Attributes attrs = conn.getMainAttributes(); System.out.println(attrs.isEmpty()); } }