Summary

A processor factory is available for the following run-time environments.

• JAVA_4
  • JDOM 1.0
  • JDOM 1.1

• JAVA_5
  • JDOM 1.0 (?)
  • JDOM 1.1

Therefore, the XVCLProcessorFactory mechanism should select a processor at runtime based upon the run-time environment. The factory class is

 gchii.tools.xvcl.XVCLProcessorFactory

Multiple, independent instances of an XVCLProcessor should be supported. See also Xvcl And Static.

JAVA_4 vs. JAVA_5

The XVCLProcessorFactory uses a mechanism (to be determined) to select JAVA_4 or JAVA_5.

• When JAVA_5, a JAVA_5-based processor is preferred. If none exists, try JAVA_4.
• When JAVA_4, find a JAVA_4-based processor. If none exists, display a meaningful error message.

JDOM 1.0 vs. JDOM 1.1

The XVCLProcessorFactory uses a mechanism (to be determined) to select JDOM 1.0 or JDOM 1.1.

• A certain class has been moved from one package to another.
  • When a certain class exists, use JDOM 1.1-compatible processor.
  • Otherwise, use JDOM 1.0-compatible processor.

Implements the IXVCLProcessor interface

An XVCLProcessor must implement this interface:

 edu.xvcl.core.api.IXVCLProcessor

XVCLAntTask

An XVCLAntTask uses the XVCLProcessorFactory to get an instance of IXVCLProcessor.

Plug-in

An XVCLProcessor is a plug-in for the XVCLProcessorFactory. The class name of a specific XVCLProcessor is unknown to the factory.

• The XVCLProcessorFactory, XVCLAntTask and its interfaces are compiled separately.
• An implementation of IXVCLProcessor is identified using the service mechanism.

Service mechanism

An XVCLProcessor implements the IXVCLProcessor interface. Therefore, the class name is stored as a resource in the edu.xvcl.core.api.IXVCLProcessor file under META-INF/service.

If our implementation were gchii.tools.xvcl3a.XVCLProcessor, the resource would be

 ----- META-INF/service/edu.xvcl.core.api.IXVCLProcessor -----
 gchii.tools.xvcl3a.XVCLProcessor