Module java.jms
![](https://bcentral-packageicons.azureedge.net/images/ballerinax_java.jms_0.1.1.png)
ballerinax/java.jms Ballerina library
Overview
The ballerinax/java.jms
module provides an API to connect to an external JMS provider like ActiveMQ from Ballerina.
This module is created with minimal deviation from the JMS API to make it easy for the developers who are used to working with the JMS API. This module is written to support both JMS 2.0 and JMS 1.0 API.
Currently, the following JMS API Classes are supported through this module.
- Connection
- Session
- Destination (Queue, Topic, TemporaryQueue, TemporaryTopic)
- Message (TextMessage, MapMessage, BytesMessage)
- MessageConsumer
- MessageProducer
The following sections provide details on how to use the JMS connector.
Samples
JMS message Producer
The following Ballerina program sends messages to a queue named MyQueue.
import ballerinax/java.jms; public function main() returns error? { jms:Connection connection = check new ( initialContextFactory = "org.apache.activemq.jndi.ActiveMQInitialContextFactory", providerUrl = "tcp://localhost:61616" ); jms:Session session = check connection->createSession({acknowledgementMode: "AUTO_ACKNOWLEDGE"}); jms:Destination queue = check session->createQueue("MyQueue"); jms:MessageProducer producer = check session.createProducer(queue); jms:TextMessage msg = { content: "Hello Ballerina!" }; check producer->send(msg); }
JMS message consumer
The following Ballerina program receives messages from a queue named MyQueue.
import ballerinax/java.jms; import ballerina/log; public function main() returns error? { jms:Connection connection = check new ( initialContextFactory = "org.apache.activemq.jndi.ActiveMQInitialContextFactory", providerUrl = "tcp://localhost:61616" ); jms:Session session = check connection->createSession({acknowledgementMode: "AUTO_ACKNOWLEDGE"}); jms:Destination queue = check session->createQueue("MyQueue"); jms:MessageConsumer consumer = check session.createConsumer(queue); while true { jms:Message? response = check consumer->receive(3000); if response is jms:TextMessage { log:printInfo("Message received: ", content = response.toString()); } } }
Asynchronous message consumer
One of the key deviations from the JMS API was the asynchronous message consumption using message listeners. In Ballerina transport listener concept is covered with service type, hence we have used the Ballerina service to implement the message listener. Following is a message listener example listening on a queue named MyQueue.
import ballerina/log; import ballerinax/java.jms; service "consumer-service" on new jms:Listener( connectionConfig = { initialContextFactory: "org.apache.activemq.jndi.ActiveMQInitialContextFactory", providerUrl: "tcp://localhost:61616" }, sessionConfig = { acknowledgementMode: "AUTO_ACKNOWLEDGE" }, destination = { 'type: jms:QUEUE, name: "MyQueue" } ) { remote function onMessage(jms:Message message) returns error? { if message is jms:TextMessage { log:printInfo("Text message received", content = message.content); } } }
Adding the required dependencies
Add the required dependencies to the Ballerina.toml
file based on the broker that you're trying to connect to.
Add the configurations below to run the given examples using Apache ActiveMQ
.
[[platform.java11.dependency]] groupId = "org.apache.activemq" artifactId = "activemq-client" version = "5.18.2" [[platform.java11.dependency]] groupId = "org.apache.geronimo.specs" artifactId = "geronimo-j2ee-management_1.1_spec" version = "1.0.1" [[platform.java11.dependency]] groupId = "org.fusesource.hawtbuf" artifactId = "hawtbuf" version = "1.11"