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A message is just a record in a table which has a timestamp (which determines the ordering), and other fields.
A sender can send to a queue or a topic. A queue has a receiver pulling messages. A topic will just distribute to 1 or more queues.
Receivers need to receive the message then mark it as processed when done.
Message columns
| Column name | Description |
|---|---|
| ID | |
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| db uuid for this row |
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| HIBERNATE_VERSION_NUMBER |
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/** constant for field name for: contextId */
public static final String FIELD_CONTEXT_ID = "contextId";
/** constant for field name for: id */
public static final String FIELD_ID = "id";
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| incrementing number so two updates dont occur at once (optimistic locking) | |
| SENT_TIME_MICROS | microseconds since 1970 this message was sent (note this is probably unique, but not necessarily |
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| GET_ATTEMPT_TIME_ |
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| MILLIS | milliseconds that the message was attempted to be received |
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| GET_ATTEMPT_ |
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| COUNT | how many times this message has been attempted to be retrieved |
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| STATE | state of this message: IN_QUEUE, GET_ATTEMPTED, PROCESSED |
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| GET_TIME_MILLIS | millis since 1970 that this message was successfully received |
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| FROM_MEMBER_ID | member id of user who sent the message |
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| TO_MEMBER_ID |
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| member id of user who is receiving the message |
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| QUEUE_OR_TOPIC_NAME | queue or topic name for the |
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| message |
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| MESSAGE_BODY |
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| message body |