Interfacing to OLE 2.0

JADE enables you to interface to Object Linking and Editing (OLE 2.0) object images.

Data stored for a persistent OleObject object is compressed automatically, which significantly reduces the required storage overhead when large numbers of OleObject objects are stored. Transient OleObject objects are created for runtime use of OleControl objects. These transient objects are not compressed, as that would create an unnecessary overhead for that runtime object.

JADE provides the OleObject system class, which is used to store the Object Linking and Editing (OLE 2.0) object images for the OleControl class. The OleObject class can also be used to store programmatically controlled OLE images that are not attached to a control. (For more details, see "OleObject Class", in Chapter 1 of the JADE Encyclopaedia of Classes.)

The OleControl system class provided by JADE allows attachment of objects that are actually edited or controlled by other applications. For example, a Word document, an Excel spread sheet, a video clip, or a Paintbrush picture can be stored in JADE, but editing or playing the object invokes the controlling application. (For more details, see "OleControl Class", in Chapter 2 of the JADE Encyclopaedia of Classes.)

The OleControl class handles any object for which an OLE Server is registered in the database operating system registry. An application that is capable of being an OLE Server has a *.reg file associated with it. To load the registration information, double-click on the .reg file in the Windows Explorer.

Neither the OleObject nor the OleControl class is available in a JADE application running on a server node.

The JADE extract process extracts a definition of the OleControl object (as it does with other controls painted at design time when the form definitions are extracted) but it does not extract the user data associated with the control. It is your responsibility to extract the user data and load it into a deployed database, if required.

For example, the following objects can be handled by the OleControl class.

You can use OLE 2.0 and ActiveX controls in JADE only on the currently supported Windows operating systems. (For details, see "Software Requirements" under "Operational Requirements", in the JADE Installation and Configuration Guide.)