Java Tutorial/Network/JarURLConnection

Get the entry name; it should be the same as specified on URL

import java.net.JarURLConnection;
import java.net.URL;
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();
    String entryName = conn.getEntryName();
  }
}

When no entry is specified on the URL, the entry name is null

import java.net.JarURLConnection;
import java.net.URL;
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();
    String entryName = conn.getEntryName(); // null
  }
}