wht jar file or package does PageUtil requires

wht jar file or package does PageUtil requires

PageUtil cannot be resolved what package needed to be downloaded
****Code :
try {
RequestContext rc = PageUtil.getCurrentRequestContext(pageContext);
ManagedObject mo =ContentUtil.getManagedObject(rc.getRequestOID());
}**
Error : 1.PageUtil and ContentUtil cannot be found 2. The method
getRequestOID() is undefined for the type RequestContext, ManagedObject
cannot be resolved to a type, ContentUtil cannot be resolved