Springboot websocket multiple chat rooms

how to broadcast their messages to specific groups in the websocket of springboot, just as we usually chat in groups. My messages in this group cannot be received to people in other groups

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Mar.12,2021

each group should have its own URL, right? Can't I broadcast the message with @ SendTo ("/ group/ {groupId}")?

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3d797-2c392.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3d797-2c392.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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