Loading a Class That Is Not on the Classpath : ClassPath « Reflection « Java Tutorial

A URLClassLoader can be used to load classes in any directory.

import java.io.File;
import java.net.URL;
import java.net.URLClassLoader;

public class Main {
  public static void main(String[] argv) throws Exception {
    File file = new File("c:\\");

    URL url = file.toURI().toURL(); 
    URL[] urls = new URL[] { url };

    ClassLoader cl = new URLClassLoader(urls);

    Class cls = cl.loadClass("com.mycompany.MyClass");

7.11.1.Loading a Class That Is Not on the Classpath
7.11.2.Get the path from where a class is loaded
7.11.3.Obtain from where a Class is loaded
7.11.4.Load the class source location from Class.getResource()
7.11.5.Returns a reference to a file with the specified name that is located somewhere on the classpath.