package com.atlassian.plugin.classloader;
   
   import java.io.IOException;
   import java.net.URL;
   import java.util.Collections;
   import java.util.Enumeration;
   
   /**
    * An abstract class loader to show what you need to implement.
   */
  abstract class AbstractClassLoader extends ClassLoader {
      protected AbstractClassLoader(ClassLoader parent) {
          super(parent);
      }
  
      protected AbstractClassLoader() {
          super();
      }
  
      protected abstract URL findResource(String name);
  
      protected abstract Class findClass(String className) throws ClassNotFoundException;
  
      /**
       * The default implementation returns a "singleton" enumeration over the result
       * of {@link #findResource(String)}.
       *
       * @param name the name of the resource
       * @return an enumeration over all matching resources
       * @throws IOException This implementation will not throw this exception
       */
      protected Enumeration<URL> findResources(String name) throws IOException {
          final URL url = this.findResource(name);
          return url != null ? Collections.enumeration(Collections.singleton(url)) : null;
      }
  }