java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.io.File.delete()' on a null object reference

[seven001]

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Bug exists Release Version 1.2.5 (Java Repository Master Branch)

Thread Name: 'MQTT Rec: cb7b3027222045a186dfe7fc43a9f35f'
Back traces starts.
java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.io.File.delete()' on a null object reference
at i.b.a.a.a.a0.b.clear(MqttDefaultFilePersistence.java:4)
at org.eclipse.paho.client.mqttv3.internal.ClientState.clearState(ClientState.java:2)
at org.eclipse.paho.client.mqttv3.internal.ClientState.notifyReceivedAck(ClientState.java:26)
at org.eclipse.paho.client.mqttv3.internal.CommsReceiver.run(CommsReceiver.java:22)
at java.lang.Thread.run(Thread.java:929)
Back traces ends.

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