title: Java - Cannot find symbol?
body: <p>I've practicing a little here but I just can't figure it out. I declared the <strong>ArrayList <em>ns</em></strong> but it cannot be found: 
  <strong>error: cannot find symbol ns.Add(aa);</strong>
   Why? Sure that I simply don't see something obvious. </p>
  
  <pre><code>import javax.swing.*;
  import java.awt.*;
  import java.awt.image.*;
  import java.awt.event.*;
  import java.util.Random;
  import java.util.*;
  import java.io.*;
  
  
  public class Pixels6 extends JFrame
  {   
  static java.util.List ns = new ArrayList();
  
  
  class PaintingComponent extends JPanel
  {
      public void paintComponent(Graphics g)
      {
          super.paintComponent(g);
          setBackground(Color.black);
      } 
  } 
  
  public static void main( String[] args ) throws InterruptedException, IOException
  
  { 
      try
      {
              fl = new FileInputStream("test_for_java2.s8");
              aa = fl.read(); 
  
      javax.swing.Timer swTimer = new javax.swing.Timer( 10, new ActionListener()
      {
          public void actionPerformed(ActionEvent ae)
          {               
              if (aa!=-1)
              {
                  aa -= 128;  
                  aa = -aa; 
                  ns.Add(aa);
                  try 
                      {aa=fl.read(); }    
                  catch( IOException e )
                  {   
                      System.out.println( "Access denied: " + e );
                      System.out.println( e );
                  }  
              }
              else    try 
                      {fl.close();} 
                  catch( IOException e )
                  {
                      System.out.println( "Access denied: " + e );
                      System.out.println( e );
                  } 
          } /// Action
  
      }); /// Timer
      swTimer.start();
  
      } //try
  
      catch( IOException e )
          {
              System.out.println( "Access denied: " + e );
              System.out.println( e );
          }
  
  
      SwingUtilities.invokeLater( new Runnable()
      {
          public void run()
          {
              new Pixels6().setVisible(true);
          }
      });
  
  } /// main
  
  } /// Pixels6 extends JFrame
  </code></pre>