Is java client of PAHO proxy aware and enables sen

Question

Organization provides http proxy and https proxy.

If not within enterprise network successfully establishing a secure connection (ssl://brokerhost:brokerport)
1.Passing relevant keystore and truststore
2.Setting default instance of SSLSocketFactory in MqttConnectOptions.

Answer 1

No, for native MQTT there is no way to use a HTTP/HTTPS proxy.

You can not use a HTTP proxy to transport an arbitrary TCP based protocol. You need something like SOCKS (ssh can be used to to setup socks proxies or to do port forwarding to remote [not the ssh host] location)