java - how to clear ALL retained mqtt messages from mosquitto -

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i've seen mosquitto_pub -h [server] -r -n -t [xyz] syntax clearing out 1 off messages. problem device developers have posted lot of garbage messages. have java/paho code base i'd modify automatically needed, can't seem publish 0 byte message. tried

client.publish(topic,null);

but didn't seem work.

any suggestions on how delete everything, en mass.

there 2 options using paho client code depending on of 2 publish methods use.

mqttmessage msg = new mqttmessage(new byte[0]); msg.setretained(true); client.publish(topic, msg);

or

client.publish(topic, new byte[0],0,true);

the other option stop mosquitto , delete persistence file , restart


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