Using the AQ adapter to consume messages from the database

In this recipe, we will configure an inbound AQ adapter, so that it can be used to consume messages from a queue implemented in the database by Oracle AQ. The adapter will be used from a proxy service as shown in the following screenshot:

The queue EVENT_QUEUE that we will use has been set up with the OSB Cookbook standard environment using the following SQL and PL/SQL code:

--creating the object type, which defines payload 
CREATE OR REPLACE TYPE event_typ as OBJECT
(
   id NUMBER(19)
   , event_type VARCHAR2(30)
   , event_time TIMESTAMP
)

-- creating queue table
BEGIN
  sys.dbms_aqadm.create_queue_table(
           queue_table => 'EVENT_QUEUE_T',
           queue_payload_type => 'OSB_COOKBOOK.EVENT_TYP',
           sort_list => 'ENQ_TIME',
           compatible => '10.0.0',
           primary_instance => 0,
           secondary_instance => 0,
           storage_clause => 'tablespace USERS pctfree 10 initrans...