JPanel doesn't paint graphics

Question

Hi ! I've been writing a program that should graph a linear function, the problem is that I'm trying to draw a line in a JPanel but this doesn't work XD...The program has 2 windows. The first one is the windows from where i get data for the function, after having the data I press a button that I want to open a new window and draw the function...
This is the part of the code in the button on the first window that certainly opens a new window
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
   JFrame frm_grafica = new JFrame("Grafica - B-Rabbit");
   frm_grafica.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   Grafica graph = new Grafica();   
   frm_grafica.getContentPane().add(graph);
   frm_grafica.setSize(250,250);
   frm_grafica.setLocation(this.getLocation().x+this.getWidth()+5, this.getLocation().y);
   frm_grafica.setVisible(true);
}but in the new window [that is located beside the first window] this is the code, that doesn't work...yes maybe there's something i don't do or something that i am passing over..
public class Grafica extends JPanel{
    Grafica(){
        this.setBackground(Color.WHITE);
    protected void PaintComponent(Graphics g){
        super.paint(g);
        g.setColor(Color.BLACK);
        g.drawLine(50,50, 20, 20);
}So Hope someone helps me...

Answer 1

//protected void PaintComponent(Graphics g){
protected void paintComponent(Graphics g){//<-- it's 2.00am, small p
        //super.paint(g);
        super.paintComponent(g);