+/**
+ *
+ * Implements both archetype and implementation of a given process.
+ *
+ * At specification time, <code>executionSpec</code> represents the spec of the
+ * parameters accepted by the process, with, among others: type, default value
+ * and, optionally, possible values for each parameter. Thus ExecutionSpec might
+ * be a huge object. Note that when marshalling only a reference to a specific
+ * ExecutionSpec is stored in the XML to optimize performance and avoid
+ * redundancy between various ExecutionFlowDesciptor that might have the same
+ * ExecutionSpec.
+ *
+ * At runtime, we build a RealizedFlow which references an
+ * ExecutionFlowDescriptor. As it happens AFTER marshalling / unmarshalling
+ * process, the ExecutionSpec is null but we manage to retrieve the
+ * ExecutionSpec and store it in the RealizedFlow, whereas set values of the
+ * parameters are stored in the <code>values</code> map.
+ *
+ * Generally, values object are either a <code>PrimitiveAccessor</code> or a
+ * <code>RefValue</code> but can be other objects.
+ */
+public class ExecutionFlowDescriptor implements Serializable {
+ private static final long serialVersionUID = 7101944857038041216L;