OSCore is a set of small utility classes that are useful in J2EE and even non-J2EE applications. Components include utilities to modify text, dates, primitive data, and XML. Also included is an EJB-compatible sequence generator that can easily be used by entity beans to provide unique IDs for primary keys.
OpenSymphony Workflow is a very flexible workflow system that can be plugged in to almost any need or existing application. Uses can range from document management to order processing to project management. It includes support for many different interface mechanisms (SOAP, EJB, Java Class) as well as persistence (EJB, JDBC, XMl, Ofbiz). It works in any J2EE container, including servlet containers (without EJB support).
XWork is a generic command pattern implementation and inversion of control (IoC) container. It is designed to be small, fast, and fit specifically for workflow-related usages, such as Web application frameworks and workflow engines. It provides the foundation for WebWork, a Java-based Web framework.