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.
Prerequisites
- 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
java
folder. -
To run the example, enter:
./run.sh processchangeeventheader.ProcessChangeEventHeader
- 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 thechangedFields
bitmap field. It lists the two fields that were changed: theDescription
field that you changed, and theLastModifiedDate
field that the system changed. For example: