Oracle Advanced Queue v Javě

1) Přihlaste se do databáze Oracle a vytvořte uživatele.

CREATE USER jmsuser IDENTIFIED BY a;
GRANT DBA, AQ_ADMINISTRATOR_ROLE, AQ_USER_ROLE to jmsuser;
GRANT EXECUTE ON DBMS_AQADM TO jmsuser;
GRANT EXECUTE ON DBMS_AQ TO jmsuser;
GRANT EXECUTE ON DBMS_LOB TO jmsuser;
GRANT EXECUTE ON DBMS_JMS_PLSQL TO jmsuser;

2) Třída vytvoří frontu pro více spotřebitelů a zaregistruje dva účastníky do fronty. (ConnectionDefinition.getOracleConnection() vrátí běžné připojení jdbc k oracle)

import java.sql.Connection;
import oracle.AQ.AQAgent;
import oracle.AQ.AQDriverManager;
import oracle.AQ.AQQueue;
import oracle.AQ.AQQueueProperty;
import oracle.AQ.AQQueueTable;
import oracle.AQ.AQQueueTableProperty;
import oracle.AQ.AQSession;

/**
 *
 * @author alukasiewicz
 */
public class NewClass {

    public static void main(String[] args) throws Exception {
        Class.forName("oracle.AQ.AQOracleDriver");
        Connection con = ConnectionDefinition.getOracleConnection();
        AQSession aq_sess = AQDriverManager.createAQSession(con);
        AQQueueTableProperty qtable_prop;
        AQQueueProperty queue_prop;
        AQQueueTable q_table;
        AQQueue queue;
        AQAgent subs1, subs2;
        qtable_prop = new AQQueueTableProperty("SYS.AQ$_JMS_BYTES_MESSAGE");
        qtable_prop.setMultiConsumer(true);
        q_table = aq_sess.createQueueTable("jmsuser", "aq_table5", qtable_prop);
        queue_prop = new AQQueueProperty();
        queue = aq_sess.createQueue(q_table, "aq_queue5", queue_prop);
        System.out.println("Successful createQueue");
        System.out.println("Successful start queue");
        subs1 = new AQAgent("GREEN", "", 0);
        subs2 = new AQAgent("BLUE", "", 0);
        queue.addSubscriber(subs2, null);
        queue.addSubscriber(subs1, null);
        queue.start();
    }
}

3) Třída publikuje zprávy do fronty.

    public class Publisher {

        public static void main(String[] args) throws Exception {
            Class.forName("oracle.AQ.AQOracleDriver");
            Connection con = ConnectionDefinition.getOracleConnection();
            TopicConnection tc_conn =AQjmsTopicConnectionFactory.createTopicConnection(con);
            tc_conn.start();
            TopicSession jms_sess = tc_conn.createTopicSession(true, Session.SESSION_TRANSACTED);
            Topic queueTopic= ((AQjmsSession )jms_sess).getTopic("JMSUSER","AQ_QUEUE5");
            AQjmsTopicPublisher publisherAq = (AQjmsTopicPublisher)jms_sess.createPublisher(queueTopic);
            BytesMessage messAll = jms_sess.createBytesMessage();
            BytesMessage messOnlyForGreen = jms_sess.createBytesMessage();
            messAll.writeUTF("Message for all subscribers");
            messOnlyForGreen.writeUTF("Message only for green");
            publisherAq.publish(messAll);
            publisherAq.publish(messOnlyForGreen, new AQjmsAgent[]{new AQjmsAgent("GREEN", null)} );
            con.commit();
            tc_conn.close();
            con.close();                
        } 
    }

V oracle můžete tyto zprávy zobrazit ve frontě. Dvě za zelenou jednu za červenou.

    SELECT a.queue,  a.msg_state, a.consumer_name FROM jmsuser.aq$aq_table5 a

4) Třída čte zprávu z fronty;

public class Subscriber {

    public static void main(String[] args) throws Exception {
        Class.forName("oracle.AQ.AQOracleDriver");
        Connection con = ConnectionDefinition.getOracleConnection();
        TopicConnection tc_conn = AQjmsTopicConnectionFactory.createTopicConnection(con);
        TopicSession jms_sess = tc_conn.createTopicSession(true, Session.SESSION_TRANSACTED);
        tc_conn.start();
        Topic queueTopic = ((AQjmsSession) jms_sess).getTopic("jmsuser", "AQ_QUEUE5");
        TopicSubscriber subGreen =  (TopicSubscriber)((AQjmsSession) jms_sess).createDurableSubscriber(queueTopic, "GREEN");
        TopicSubscriber subRed =  (TopicSubscriber)((AQjmsSession) jms_sess).createDurableSubscriber(queueTopic, "RED");        
        Message msg = subGreen.receive(10);
        System.err.println("Start receiving message for green subscriber");
        while(msg != null){
              System.err.println("     GREEN recive message "+ ((BytesMessage)msg).readUTF());
              msg = subGreen.receive(10); // receive with timeout;
        }
        System.err.println("End receiving message for green subscriber");
        System.err.println("  ");        
        System.err.println("Start receiving message for red subscriber");
        BytesMessage byteMsg = (BytesMessage)msg;
        msg = subRed.receive(10);
        while(msg != null){
              System.err.println("     RED recive message "+ ((BytesMessage)msg).readUTF());
              msg = subRed.receive(10); // receive with timeout;
        }
           System.err.println("End receiving message for red subscriber");
        con.commit();
        tc_conn.close();
        con.close();

    }
}

5) Závislosti Pom

 <dependencies>
        <dependency>
            <groupId>com.oracle</groupId>
            <artifactId>ojdbc6</artifactId>
            <version>11.2.0.4</version>
        </dependency>
        <dependency>
            <groupId>com.oracle</groupId>
            <artifactId>aqapi</artifactId>
            <version>13</version>
        </dependency>
        <dependency>
            <groupId>javax.jms</groupId>
            <artifactId>jms</artifactId>
            <version>1.1</version>
        </dependency>
        <dependency>
            <groupId>javax.transaction</groupId>
            <artifactId>jta</artifactId>
            <version>1.1</version>
        </dependency>
        <dependency>
            <groupId>com.oracle</groupId>
            <artifactId>orai18n</artifactId>
            <version>11.2.0.4</version>
        </dependency>
    </dependencies>