publish message in main class instead of talker

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Hi all,

I'm working on a project that receives data from a sensor and sends the data back to pc using rosjava.

I'm trying to realize this function on the base of rosjava_tutorial_pubsub. I realized almost all the tutorials tend to use NodeMainExecute to run a node, and the publish function is implemented in the Talker.java itself.

Since my data are retrieved and stored in the main class and updates constantly, i want to publish my message in main class, which means moving the following snippet from talker.java into main.java.

org.ros.message.std_msgs.String str = publisher.newMessage();
str.data = mdata;
publisher.publish(str);

how should I modify the main.java? Should I add a variable Publisher publisher in the beginning?

actually I want to run roscore on PC.