de.danet.an.workflow.omgcore

This package defines the core domain of a workflow management system. It is an adaption of the OMG "Workflow Management Facility Sepcification, V1.2". We consider the interfaces and classes in this package (together with the interfaces and classes in the {@link de.danet.an.workflow.api extended API}) to be useable as a general Java workflow API, i.e. if there was a JSR for a Java workflow API, we think the merger of these two packages would be a good starting point.

We have tried to follow the original specification as close as possible. However, some conventions used by OMG do not fit in the Java environment and changes have been made accordingly.

The main differences are:

• OMG separates words in identifiers using underscores. In the Java environment, words are delimited by using a capital letter.
• The pattern for relationships has been replaced by a single access method RELNAMEs that returns a collection (the plural "s" has been omitted from the relation history of interface {@link de.danet.an.workflow.omgcore.WfExecutionObject WfExecutionObject} for gramatical reasons).
• The OMG model introduces a class WfEventAudit. While the collection of WfEventAudits may be considered the result of an audit, we think that individual items are rather WfAuditEvents. This conforms better to the Java naming scheme where event classes end with "...Event" and the corresponding listener interfaces with "...Listener".
• We have appended "...Exception" to the names of the exceptions, as is usual in Java. Additionally, we have put the exceptions in a separate sub-package to avoid naming conflicts when all omgcore classes are imported with a wildcard import.
• There are no enumeration types in Java. While, in general, elements of enumeration types can simply be mapped to constant definitions, we have not followed this approach in all cases.
  • In the Java environment, the states and substates of an execution object can conveniently be modelled as a {@link de.danet.an.workflow.omgcore.WfExecutionObject.State class hierarchy}. This provides type safe usage and allows to define some convenient methods for handling state.

We have, however not changed the following:

• The access method for attributes have not been renamed getAttribute(). The getX()/setX(...) pattern has been introduced by JavaBeans for the configuration of component properties, not as a general mechanism to access attributes. The properties used in the OMG model are dynamic data properties, not configuration options. Therefore, there is no reason why they should follow the getX()/setX(...) pattern

The documentation of classes and methods in this package consists mostly of an abbreviated version of the description provided by OMG's "Workflow Management Facility Specification, V1.2". Unless otherwise stated, the description from the specification applies fully, i.e. you can use the specification to obtain a detailed understanding of the functionallity provided.

The following picture shows the complete model.

The OMG specification defines that the data type is specified by its "IDL type represented by its string name".

A WfAuditEvent provides an audit record of workflow event information.

It provides information on the source of the event and contains specific event data.