SAX sucks

Main.java

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;

public class Main {

    public static void main(String[] args) {
        try {
            URL[] classUrls = {new URL("file:///path/to/jar/with/separate-main.jar")};
            ClassLoader oldcl = Thread.currentThread().getContextClassLoader();
            URLClassLoader urlcl = new URLClassLoader(classUrls, oldcl);
            Class sepMain = Class.forName("SeparateMain", true, urlcl);
            Object instance = sepMain.newInstance();
            Method do_stuff = sepMain.getDeclaredMethod("do_stuff");
            do_stuff.invoke(instance);
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        }
    }
}

ouput.txt

SeparateMain.do_stuff
java.lang.reflect.InvocationTargetException
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:564)
	at Main.main(Main.java:43)
Caused by: org.xml.sax.SAXException: SAX2 driver class org.apache.xerces.parsers.SAXParser not found
java.lang.ClassNotFoundException: org.apache.xerces.parsers.SAXParser
	at java.xml/org.xml.sax.helpers.XMLReaderFactory.loadClass(XMLReaderFactory.java:200)
	at java.xml/org.xml.sax.helpers.XMLReaderFactory.createXMLReader(XMLReaderFactory.java:191)
	at SeparateMain.do_stuff(SeparateMain.java:9)
	... 5 more
Caused by: java.lang.ClassNotFoundException: org.apache.xerces.parsers.SAXParser
	at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:582)
	at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:190)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499)
	at java.xml/org.xml.sax.helpers.NewInstance.newInstance(NewInstance.java:91)
	at java.xml/org.xml.sax.helpers.XMLReaderFactory.loadClass(XMLReaderFactory.java:198)
	... 7 more

SeparateMain.java

import org.xml.sax.SAXException;
import org.xml.sax.helpers.XMLReaderFactory;

import static java.lang.Class.forName;

public class SeparateMain {
    public void do_stuff() throws ClassNotFoundException, IllegalAccessException, InstantiationException, SAXException {
        System.out.println("SeparateMain.do_stuff");
        XMLReaderFactory.createXMLReader("org.apache.xerces.parsers.SAXParser");
    } 
}
// This should be compiled to a jar which should also include classes from xercesImpl.jar