Symbol Not Found

Question

I've just started swing, and had a few promising results, until my code got a little more complex. I've run into a problem, and I don't know enough to really understand why it's there. Basically, I have some code (which I will paste here after my explanation) that is supposed to create a window and add in a text area and text field. The problem is, the JPanel and JScrollPane variables aren't recognized as existent by the compiler. I can seem to figure out why.
Here's the entire code I'm working with:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class TerraGUI {
     private static void createAndShowGUI() {
          JFrame frame = new JFrame("Main Window");
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          JPanel mainPane = new JPanel();
          mainPane.setPreferredSize(new Dimension(800, 600));
          frame.getContentPane().add(mainPain);
          JScrollPane chatPain = new JScrollPane();
          chatPain.setVerticalAlignment(JLabel.BOTTOM);
          JTextField textField = new JTextField(20);
          JTextArea textArea = new JTextArea();
          textArea.setColumns(50);
          textArea.setRows(10);
          textArea.setEditable(false);
          chatPane.add(textArea);
          chatPane.add(textField);
          frame.getContentPane().add(chatPain);
          frame.pack();
          frame.setVisible(true);
     public static void main(String[] args) {
          SwingUtilities.invokeLater(new Runnable() {
               public void run() {               
                    createAndShowGUI();
}And here's the compiler errors:
C:\Program Files\Java\jdk1.6.0_16\bin\javac "TerraGUI.java" (in directory: C:\Users\Cyle Dawson\Documents\Java\Terra)
TerraGUI.java:12: cannot find symbol
symbol  : variable mainPain
location: class TerraGUI
  frame.getContentPane().add(mainPain);
                             ^
TerraGUI.java:15: cannot find symbol
symbol  : method setVerticalAlignment(int)
location: class javax.swing.JScrollPane
  chatPain.setVerticalAlignment(JLabel.BOTTOM);
          ^
TerraGUI.java:21: cannot find symbol
symbol  : variable chatPane
location: class TerraGUI
  chatPane.add(textArea);
  ^
TerraGUI.java:22: cannot find symbol
symbol  : variable chatPane
location: class TerraGUI
  chatPane.add(textField);
  ^
4 errors
Compilation failed.Can anyone explain to me why the variables aren't recognized? I'm supposed to have a small, semi-functioning GUI by Sunday and this is confounding me.

Answer 1

I noticed. I have like 9 API windows up and I got them confused. I'm having a rough time with simple mix ups.
I'll look at the layout manager and hopefully get that part sorted out.
I ran into another problem. I don't think I'm grasping exactly how to use Panels and Scroll Panes. I've edited my code a little (I will paste the new bit below), and maybe you can help.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class TerraGUI {
     private static void createAndShowGUI() {
          JFrame frame = new JFrame("Main Window");
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          JPanel mainPane = new JPanel();
          mainPane.setPreferredSize(new Dimension(800, 600));
          JTextField textField = new JTextField(20);
          mainPane.add(textField);
          frame.getContentPane().add(mainPane); //Line A
          JTextArea textArea = new JTextArea("BlahBlah");
          textArea.setColumns(50);
          textArea.setRows(10);
          textArea.setEditable(false);
          JScrollPane chatPane = new JScrollPane();
          chatPane.add(textArea);
          frame.getContentPane().add(chatPane); //Line B
          frame.pack();
          frame.setVisible(true);
     public static void main(String[] args) {
          SwingUtilities.invokeLater(new Runnable() {
               public void run() {               
                    createAndShowGUI();
}I'm basically trying to get a text field and a text area in the window. I'll work on the positioning when I get them to load. What's been happening is I can get either the JPanel or the JScollPane to load, but not both. In other words, if I comment the line labeled Line A out and leave Line B, I will get my text area, and vice versa, if I comment Line B and leave Line A, I get my text field. When I try both, my window has no size or content. I want the text area to be able to have scroll bars, and that's why I need it in a scroll pane.
I really think I'm missing something important in the concepts department of using Swing.