JFrame in GUI class not updating - swing

Question

I am very new to JAVA, and am attempting to write a pharmacokinetics calculation program for my students to use.
The program reads a database of plasma concentration vs time values and calculates a number of pharmacokinetic parameters and outputs these into a number of frames, as well as drawing linear and exponential curves which are also output into frames.
I wrote the program initially as a console based, to make sure everything worked as required, before moving to GUI. Now comes the difficult steps of GUI building. I realize my console code will change considerably, I'm looking forward to the learning curve.
I am now attempting to output results via a separate 'GUI' class, and so pass frames between classes before output. I have tried to pass a frame from my 'GUI' class to my other class, without success.
In my attempt to learn GUI, and the class structure of JAVA, I have two classes.
A ProjectChart Class, that contains all the calculation and graphing methods.
A ProjectChartGUI class, which will eventually be used to output all data.
ProjectChartGUI currently defines a number of InternalFrames. I have been trying to pass one such internalframe to a function in ProjectChart, OutputInputData(). This constructs a table of data, read by a separate function, and will output this table into a frame for user validation.
I am trying to pass a JInternalFrame from ProjectChartGUI to OutputInputData().
Initially I passed the JInternalFrame using a .getFrame() function using OutputInputData (JInternalFrame frame).
I also tried to pass a ProjectchartGUI object. OutputInputData (ProjectChartGUI tProjectChartGUI). This also did not work.
In both cases, the program runs, all calculations are performed successfully, however the frame which opens via ProjectChartGUI is empty.
Here is my main:
public static void main(String[] args) throws IOException, InterruptedException, URISyntaxException{
ProjectChartGUI tGUI = new ProjectChartGUI();
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
ActionPharmacokinetics(tGUI);
tGUI.setVisible(true);
}
});
}
Here is a snippet of the function ActionPharmacokinetics():
public static void ActionPharmacokinetics(ProjectChartGUI tGUI){
DetermineUserInput();
if(CHECK == IVBOLUS_TRUE)
{
// Read database to access main information
Access_IVBOLUS_DatabaseList();
// Read database again to allow user to select desired entry for calculation
Access_IVBOLUS_Database();
// Output CP and T values to a new window for confirmation
OutputInputData(tGUI);
//Diplay Linear chart of Data
Display_IVBOLUS_LinearGraph();
// Display exponential chart of Data
Display_IVBOLUS_ExponentialGraph();
// Calculate pharmacokinetic parameters
Calculate_IVBOLUS_PharmacokineticParameters();
// Output pharmacokinetic paramaters
OutputPharmacokineticParamaters();
}}
Here is outputInputData(): Cp, lnCp and T are declared variables in ProjectChart. Numberofpoints is the numberofdata points read from the database.
static public void OutputInputData(ProjectChartGUI tGUI){
//create table objects
String[] ColumnNames = new String[]{"Data Point", "CP"+Units_CP,"ln CP","Time"+Units_T};
double SetDecimalPoint = 0.0;
Object[][] Data = new Object[NumberofPoints][4];
for (int k=0;k<NumberofPoints;k++)
{
Data[k][0] = k+1;//index
Data[k][1] = Cp[k];//plasma
SetDecimalPoint = lnCp[k];//log plasma
BigDecimal bd = BigDecimal.valueOf(SetDecimalPoint);
bd = bd.setScale(2, BigDecimal.ROUND_FLOOR); // rounds ln cp to 2 decimal places for output
Data[k][2] = bd;
Data[k][3] = T[k];//time
}
//create table
JTable jtable = new JTable(Data, ColumnNames);
//Create frame
//JFrame jFrame = new JFrame("Input Data");
//jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//add table to frame
tGUI.getframe().add(new JScrollPane(jtable));
tGUI.getframe().pack(); //auto size
tGUI.getframe().setVisible(true);
}
.getframe() returns an internal frame from ProjectChartGUI
public javax.swing.JInternalFrame getframe(){
return jInternalFrame1;
}
I used Netbeans GUI builder to define a frame, with an internal frame
private javax.swing.JInternalFrame jInternalFrame1;
All other code in ProjectChartGUI was autogenerated by Netbeans.
Does anyone have any suggestions on where I may be going wrong?