docs(apache/activemq#1714): Add async send documentation

src/components/classic/documentation/async-sends.md

@@ -42,9 +42,37 @@ You can enable this feature on the [ActiveMQConnection](http://incubator.apache.
 ((ActiveMQConnection)connection).setUseAsyncSend(true);
 ```
 
+### JMS 2.0 CompletionListener (since 6.2.0)
+
+JMS 2.0 introduced a standard API for asynchronous sending via `CompletionListener`. 
+When you call `send(message, completionListener)`, the provider notifies your `CompletionListener` once the send completes (or fails).
+
+```java
+producer.send(message, new CompletionListener() {
+    @Override
+    public void onCompletion(Message message) {
+        // message was sent successfully
+    }
+
+    @Override
+    public void onException(Message message, Exception exception) {
+        // send failed
+    }
+});
+```
+
+**Implementation note:** the current ActiveMQ Classic implementation performs the send synchronously and then invokes the `CompletionListener` callback on a separate thread. 
+This is explicitly permitted by the JMS 2.0 specification (section 7.3). 
+Application code that follows the specification will remain compatible if a future version implements fully asynchronous sending.
+
+For high-throughput asynchronous sending outside the JMS specification, the ActiveMQ-specific `useAsyncSend` flag described above remains available and provides true non-blocking behaviour.
+
+See also the [JMS 2.0 implementation status](jms2) page for the full list of supported features.
+
 ### Also see
 
 *   [Connection Configuration URI](connection-configuration-uri)
 *   [Should I use transactions](should-i-use-transactions)
 *   [Consumer Dispatch Async](consumer-dispatch-async)
+*   [JMS 2.0 Support](jms2)
 

src/components/classic/documentation/jms2.md

@@ -63,18 +63,18 @@ The implementation approach is subject to change. Be sure to verify features in
 
 User feedback is welcome! Please comment on the JIRAs with questions and comments.
 
-JIRA|Status|Target Version|Completed Version|Feature|Notes
----|:---:|---|---|---|---
-[AMQ-7309](https://issues.apache.org/jira/browse/AMQ-7309) | ✅ | 5.16.0 | 5.18.0 | JMS 2.0 API dependency | ActiveMQ will ship with a JMS 2.0 dependency jar
-[AMQ-8322](https://issues.apache.org/jira/browse/AMQ-8322) | ✅ | 5.17.0 | 5.18.0 | `JMSContext`, `JMSConsumer`, `JMSProducer`, & `JMSRuntimeException` | Simplified JMS API support
-[AMQ-8321](https://issues.apache.org/jira/browse/AMQ-8321) | ✅ | 5.18.0 | 5.18.0 | GetBody/isBodyAssignable | Support for checking body type using a `Class<?>`
-[AMQ-8325](https://issues.apache.org/jira/browse/AMQ-8325) | ✅ | 5.18.3, 6.0.0 | 5.18.3, 6.0.0 | XA Connection methods | Updated methods when using XA transactions
-[AMQ-8494](https://issues.apache.org/jira/browse/AMQ-8494) | ✅ | 5.17.1 | 5.18.0 | Implement `CLIENT_ACKNOWLEDGEMENT` mode | Client ack requires special handling w/ the simplified JMSContext API
-[AMQ-8464](https://issues.apache.org/jira/browse/AMQ-8464) | ❌ | 6.4.0 | | JMSConsumer | `.receiveBody(Class<T>)` methods
-[AMQ-8320](https://issues.apache.org/jira/browse/AMQ-8320) | ❌ | 6.3.0 | | Delivery Delay | Support for Message DeliveryDelay feature
-[AMQ-8324](https://issues.apache.org/jira/browse/AMQ-8324) | ❌ | 6.4.0 | | JMSProducer features | `CompletionListener` async send support
-[AMQ-8323](https://issues.apache.org/jira/browse/AMQ-8323) | ❌ | | | Shared Topic Consumer | Multi-consumer (queue-like) consuming from topic subscriptions
-[AMQ-9451](https://issues.apache.org/jira/browse/AMQ-9451) | ❌ | 6.5.0 | | Pooled `ConnectionFactory` | Support for JMSContext in activemq-jms-pool
+JIRA|Status|Target Version| Completed Version |Feature|Notes
+---|:---:|---|-------------------|---|---
+[AMQ-7309](https://issues.apache.org/jira/browse/AMQ-7309) | ✅ | 5.16.0 | 5.18.0            | JMS 2.0 API dependency | ActiveMQ will ship with a JMS 2.0 dependency jar
+[AMQ-8322](https://issues.apache.org/jira/browse/AMQ-8322) | ✅ | 5.17.0 | 5.18.0            | `JMSContext`, `JMSConsumer`, `JMSProducer`, &amp; `JMSRuntimeException` | Simplified JMS API support
+[AMQ-8321](https://issues.apache.org/jira/browse/AMQ-8321) | ✅ | 5.18.0 | 5.18.0            | GetBody/isBodyAssignable | Support for checking body type using a `Class<?>`
+[AMQ-8325](https://issues.apache.org/jira/browse/AMQ-8325) | ✅ | 5.18.3, 6.0.0 | 5.18.3, 6.0.0     | XA Connection methods | Updated methods when using XA transactions
+[AMQ-8494](https://issues.apache.org/jira/browse/AMQ-8494) | ✅ | 5.17.1 | 5.18.0            | Implement `CLIENT_ACKNOWLEDGEMENT` mode | Client ack requires special handling w/ the simplified JMSContext API
+[AMQ-8464](https://issues.apache.org/jira/browse/AMQ-8464) | ❌ | 6.4.0 |                   | JMSConsumer | `.receiveBody(Class<T>)` methods
+[AMQ-8320](https://issues.apache.org/jira/browse/AMQ-8320) | ❌ | 6.3.0 |                   | Delivery Delay | Support for Message DeliveryDelay feature
+[AMQ-8324](https://issues.apache.org/jira/browse/AMQ-8324) | ✅ | 6.4.0 | 6.3.0             | JMSProducer features | `CompletionListener` async send support. Note: the current implementation performs the send synchronously and invokes the `CompletionListener` on a separate thread, which is permitted by the JMS 2.0 specification (section 7.3).
+[AMQ-8323](https://issues.apache.org/jira/browse/AMQ-8323) | ❌ | |                   | Shared Topic Consumer | Multi-consumer (queue-like) consuming from topic subscriptions
+[AMQ-9451](https://issues.apache.org/jira/browse/AMQ-9451) | ❌ | 6.5.0 |                   | Pooled `ConnectionFactory` | Support for JMSContext in activemq-jms-pool
 
 ### Feature notes