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| <body> |
| <p>Interfaces for the Taverna 2 reference manager. This replaces the |
| (badly named) DataManager and is, in effect, a version 2 of that system. |
| While these APIs are implementation neutral the intent is heavily |
| towards the use of an object relational mapping (ORM) tool such as |
| Hibernate backed by a relational database to hold the various |
| collection, external reference and error documents managed by the |
| reference manager.</p> |
| <p>For those familiar with the previous DataManager code the table |
| below shows the old class names and the equivalent (where appropriate) |
| in the new code: |
| </p> |
| <table> |
| <tr> |
| <td>DataDocument</td> |
| <td>{@link net.sf.taverna.t2.reference.ReferenceSet}</td> |
| </tr> |
| <tr> |
| <td>ReferenceScheme</td> |
| <td>{@link net.sf.taverna.t2.reference.ExternalReferenceSPI}</td> |
| </tr> |
| <tr> |
| <td>EntityIdentifier</td> |
| <td>{@link net.sf.taverna.t2.reference.T2Reference}</td> |
| </tr> |
| <tr> |
| <td colspan="2">...</td> |
| </tr> |
| </table> |
| <p>One fundamental change is a move to runtime exceptions rather |
| than checked exceptions. This follows the pattern used by Spring and |
| Hibernate. The rationale is the same as in those systems - in general |
| checked exceptions are not handled properly by client code. The loss of |
| compiler level functionality from moving to runtime exceptions is |
| countered by much higher readability of code which in itself leads to |
| more robust and reliable systems.</p> |
| <p>A second change is the availability of asynchronous versions of |
| all the critical APIs. Reference construction or translation in |
| particular can be a costly process taking substantial time to complete. |
| Synchronous versions of the get methods still exist but in general the |
| simple callback based asynchronous ones are recommended over them for |
| most applications.</p> |
| </body> |
