SecurityClass

package java.security;
Security.class
   private static Class getSpiClass(String type) {
	Class clazz = spiMap.get(type);
	if (clazz != null) {
	    return clazz;
	}
	try {
	    clazz = Class.forName("java.security." + type + "Spi");
	    spiMap.put(type, clazz);
	    return clazz;
	} catch (ClassNotFoundException e) {
	    throw (Error)new AssertionError("Spi class not found").initCause(e);
	}
    }

=>Avoiding problems of default system class loader