3.7. Updating an Object
It is possible to modify a persistent object in the same manner as normal Java with no additional coding required. Assuming that the class defines methods that can be used to set the fields, then the application simply needs to invoke these methods within a transaction. The JDO implementation automatically detects when a field of a persistent object has been modified and marks the field as “dirty.” At commit time, the dirty fields of all the modified persistent objects are written back to the datastore as part of the transaction.
The following code snippet taken from UpdateExample.java shows how to find a previously created Author instance and change its name. To validate that the name has changed in the datastore, it ...
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