Mine

import java.awt.*; 
import java.awt.event.*;
import javax.swing.*; 
import java.io.*; 
import java.util.*;

public class CatMain extends JFrame implements ActionListener
{
      JButton swap = new JButton("Add/Remove");
    String[] names = new String[310];
    String[] test = new String[62];
    String[] teachers = new String[62];
    JFrame frame = new JFrame("Creating a JList Component");
    JPanel panel = new JPanel();
    JList list = new JList(teachers);
    JList list2 = new JList(test);
    JScrollPane scroll = new JScrollPane(list);
  public CatMain(String title) throws IOException                         
  {
    
    File file = new File("schedule.txt");
    
    Scanner scan = new Scanner(file);

    int i=0;
    int q=0;
    while (scan.hasNextLine())
    {
      {
        names[i] = scan.nextLine();
      }
      i++;
    }
    for(int j=0; j < names.length;j+=5)
    {      
      teachers[q] = names[j]; 
      q++;
    }
    swap.setActionCommand("swap");
    list2.setPreferredSize(new Dimension(150,400));
    scroll.setPreferredSize(new Dimension(150,400));
    panel.add(list2);
    panel.add(swap);
    panel.add(scroll);
    
    setLayout( new FlowLayout() ); 
    add( panel ); 
    swap.addActionListener( this );
  }
  public void actionPerformed( ActionEvent evt)
  {
    if ( evt.getActionCommand().equals( "swap" ) )
    {
     String name = list.isSelected();
    }
  }
  public static void main ( String[] args ) throws IOException
  {
    CatMain demo = new CatMain( "CatMain" ) ;
    
    demo.setSize( 800, 600 );     
    demo.setVisible( true );      
  }
}