import net.bytebuddy.ByteBuddy;
import net.bytebuddy.implementation.MethodDelegation;
import net.bytebuddy.matcher.ElementMatchers;

public class PrivateMethodDelegateExample {

    private void privateMethod() {
        System.out.println("This is a private method.");
    }

    public static void main(String[] args) throws IllegalAccessException, InstantiationException {
        Class proxyClass = new ByteBuddy()
                .subclass(Object.class)
                .method(ElementMatchers.isDeclaredBy(PrivateMethodDelegateExample.class)
                        .and(ElementMatchers.named("privateMethod")))
                .intercept(MethodDelegation.to(PrivateMethodDelegateExample.class))
                .make()
                .load(PrivateMethodDelegateExample.class.getClassLoader())
                .getLoaded();

        PrivateMethodDelegateExample delegateExample = (PrivateMethodDelegateExample) proxyClass.newInstance();
        delegateExample.privateMethod();
    }
}