Step 5: Subscribe to Change Events
Even though you can use the Subscribe.java example in
genericpubsub to subscribe to change events, this client doesn't expand the bitmap fields in change events, such as the
changedFields field. Use the
ProcessChangeEventHeader.java example to subscribe to change events and perform bitmap field expansion.
- Because the ProcessChangeEventHeader example subscribes to changes for Opportunity, select Opportunity for change data capture in Setup. For more information, see Select Objects for Change Notifications in the User Interface in the Change Data Capture Developer Guide.
In a Terminal window, navigate to the
To run the example, enter:
- The example subscribes to the /data/OpportunityChangeEvent channel and captures any new or changed Opportunity records.
The example prints out logging information similar to:
In Salesforce, create an opportunity record. The change event is received and printed. For example:
Update the opportunity record. For example, add a value for
Description: "My sample opportunity." The change event for the update is received and printed. The output includes the Changed Fields section, which contains the fields that were expanded from the
changedFieldsbitmap field. It lists the two fields that were changed: the
Descriptionfield that you changed, and the
LastModifiedDatefield that the system changed. For example: