com.softwareag.mdm.service
Interface Procedure

public interface Procedure

This interface must be implemented for updating a repository and performing imports and exports in a safe way.

The procedure's execution has the following features:

• Authentication
  User is authenticated either through webMethods Master Data Manager (see ServiceContext) or via a programmatic service (see ProgrammaticService),
• Atomicity
  The updates done on the repository are either all committed or all cancelled (if execution fails).
• Structural consistency
  Execution fails if there is a "structural" error: an object to update does not exist, a value set is not compatible with the type expected or an object is created with an erroneous identifier.
• Validation
  Not "structural" errors (mainly schema facets) do not prevent the execution and the commit. Those errors are handled by validation layer. This tolerant policy allows to track and correct "light" errors afterward.
• Isolation
  A lock forbids any concurrent execution of another procedure on the same branch or version. This implies that, if procedure is executed on a branch, any concurrent updates on it are excluded.
• Durability
  All the updates done on the repository are persisted.
• Logging
  Execution of a procedure is always logged into the history.

A procedure is executed by calling one of the following methods:

• ServiceContext.execute(Procedure)
• ProgrammaticService.execute(Procedure)

See Also:

Concurrency and isolation levels

Method Summary

void	execute(ProcedureContext aContext) This method's implementation defines what this procedure actually does on the current repository.

Method Detail

execute

public void execute(ProcedureContext aContext)
             throws Exception

This method's implementation defines what this procedure actually does on the current repository.

Exception handling

If this method throws an exception, container properly handles it so as to preserve integrity: any modifications that would have been made during this method execution onto current repository (see ProcedureContext.getAdaptationHome()) is cancelled.

Furthermore, if a ProcedureContext method raises an exception then any preceding modifications made on the repository are first cancelled before this method gets the exception. This additional feature is for ensuring that repository and cache remain consistent, even if this method catches these exceptions.

Multi-threading

This method is called each time one of following methods is called: ServiceContext.execute(Procedure) or ProgrammaticService.execute(Procedure). Hence the possibility that, for a single instance of this interface, this method is called concurrently by several threads, depends indeed on the way the developper manages its Procedure instances in integrated or programmatic service.

Throws:

Exception