The two persistence standards in Java have very similar API’s on the face of it. Here we give a comparison of the method calls and their equivalent in the other API.
| Operation | JDO | JPA |
|---|---|---|
Persist Object |
pm.makePersistent() |
em.persist |
Update Object |
pm.makePersistent() |
em.merge() |
Remove Object |
pm.deletePersistent() |
em.remove() |
Retrieve Object |
pm.getObjectById() |
em.find() |
Refresh Object |
pm.refresh() |
em.refresh() |
Detach single Object |
pm.detachCopy() |
em.detach() |
Flush changes |
pm.flush() |
em.flush() |
Access transaction |
pm.currentTransaction() |
em.getTransaction() |
New Query |
pm.newQuery() |
em.createQuery() |
New Named Query |
pm.newNamedQuery() |
em.createNamedQuery() |
New SQL Query |
pm.newQuery() |
em.createNativeQuery() |