Changing JLabel Text From Anywhere In Program

I'm using NetBeans.

I have a JFrame with four JPanels, SensorLL, SensorLC, SensorCR and SensorRR. They are instances of the class SensorUI. Each has a JLabel called Sensor.

The class SensorUI has a method writeSensor that writes to the JLabel "Sensor". I will have four temperature sensors. I have not started the code to read the temperature sensors yet. I will have a timer that will run once a second. When it fires I will read the sensors and display the result in the

JLabel "Sensor" in each jPanel.

I use MyMain to call FrameDemo and create the JFrame and a method

in FrameDemo to add the JPanels using addObject.

I can use SensorLL.writeSensor will write text to JLabel Sensor while in Mymain.

Then I start the timer ReadSensor.

When it times out it calls SampleSensors

For an experiment, while in SampleSensors I try to write to the JLabel in the instance SensorLL with

SensorLL.writeSensor("xx_");

I can't because it says it can't find the symbol variable SensorLL in SampleSensors class.

How can I "get to" that JLabel text when ever I need to?

Java Code:

public class MyMain {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
//SensorUI SensorLL = null;
System.out.println("Start of main");
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
FrameDemo.createAndShowGUI();

[Code] .......