35 lines
1.2 KiB
Markdown
35 lines
1.2 KiB
Markdown
# Scheduled Messages
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Scheduled messages differ from normal messages in that they won't be
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delivered until a specified time in the future, at the earliest.
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To do this, a special property is set on the message before sending it.
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## Scheduled Delivery Property
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The property name used to identify a scheduled message is
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`"_AMQ_SCHED_DELIVERY"` (or the constant
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`Message.HDR_SCHEDULED_DELIVERY_TIME`).
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The specified value must be a positive `long` corresponding to the time
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the message must be delivered (in milliseconds). An example of sending a
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scheduled message using the JMS API is as follows.
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``` java
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TextMessage message = session.createTextMessage("This is a scheduled message message which will be delivered in 5 sec.");
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message.setLongProperty("_AMQ_SCHED_DELIVERY", System.currentTimeMillis() + 5000);
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producer.send(message);
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...
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// message will not be received immediately but 5 seconds later
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TextMessage messageReceived = (TextMessage) consumer.receive();
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```
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Scheduled messages can also be sent using the core API, by setting the
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same property on the core message before sending.
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## Example
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See the [examples](examples.md) chapter for an example which shows how scheduled messages can be used with
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JMS.
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