### Question:
ClassLoaderDefineClassPatcher { public void patch(final ClassLoader classLoaderFrom, final String pluginPath, final ClassLoader classLoaderTo, final ProtectionDomain protectionDomain) { List<byte[]> cache = getPluginCache(classLoaderFrom, pluginPath); if (cache != null) { final ClassPool cp = new ClassPool(); cp.appendClassPath(new LoaderClassPath(getClass().getClassLoader())); for (byte[] pluginBytes: cache) { CtClass pluginClass = null; try { InputStream is = new ByteArrayInputStream(pluginBytes); pluginClass = cp.makeClass(is); try { classLoaderFrom.loadClass(pluginClass.getName()); } catch (NoClassDefFoundError e) { LOGGER.trace("Skipping class loading {} in classloader {} - " + "class has probably unresolvable dependency.", pluginClass.getName(), classLoaderTo); } pluginClass.toClass(classLoaderTo, protectionDomain); } catch (CannotCompileException e) { LOGGER.trace("Skipping class definition {} in app classloader {} - " + "class is probably already defined.", pluginClass.getName(), classLoaderTo); } catch (NoClassDefFoundError e) { LOGGER.trace("Skipping class definition {} in app classloader {} - " + "class has probably unresolvable dependency.", pluginClass.getName(), classLoaderTo); } catch (Throwable e) { LOGGER.trace("Skipping class definition app classloader {} - " + "unknown error.", e, classLoaderTo); } } } LOGGER.debug("Classloader {} patched with plugin classes from agent classloader {}.", classLoaderTo, classLoaderFrom); }  void patch(final ClassLoader classLoaderFrom, final String pluginPath,
                      final ClassLoader classLoaderTo, final ProtectionDomain protectionDomain); boolean isPatchAvailable(ClassLoader classLoader);  }### Answer:
@Test public void testPatch() throws Exception { ClassLoader appClassLoader = new URLClassLoader(new URL[]{}, getClass().getClassLoader()); assertEquals("Class created in parent classloader", getClass().getClassLoader(), appClassLoader.loadClass(AnonymousClassInfo.class.getName()).getClassLoader()); new ClassLoaderDefineClassPatcher().patch(getClass().getClassLoader(), PluginManager.PLUGIN_PACKAGE.replace(".", "/"), appClassLoader, null); assertEquals("Class created in app classloader", appClassLoader, appClassLoader.loadClass(AnonymousClassInfo.class.getName()).getClassLoader()); ; }