title: NullPointerException when using KeyListener to use setText
body: <p>This is a word guessing game. The first letter is shown everytime and they rest is not. Whenever a user types I want it to change the letters on the board, here is a screenshot: <a href="http://puu.sh/7moQS.jpg" rel="nofollow">http://puu.sh/7moQS.jpg</a></p>
  
  <p>Error:</p>
  
  <pre><code>Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
  at BoardUI.keyTyped(BoardUI.java:48)
  </code></pre>
  
  <p>where line <code>BoardUI.java:48</code> is</p>
  
  <p><code>b.getLetters()[b.position(b.getCurrentRow(), b.getCurrentColumn())].setText(typed + "");</code></p>
  
  <p>Game.java</p>
  
  <pre><code>public class Game {
  }
  </code></pre>
  
  <p>testGUI.java</p>
  
  <pre><code>public class testGUI {
  public static void main(String[] args) {
      new GUI("Lingo");
  }
  }
  </code></pre>
  
  <p>BoardUI.java</p>
  
  <pre><code>import javax.swing.*;
  import java.awt.*;
  import java.awt.event.KeyEvent;
  import java.awt.event.KeyListener;
  
  public class BoardUI extends JPanel implements KeyListener {
  
  private final Game game;
  private Board b = new Board();
  private Color hoverColor = new  Color(100, 100, 255);
  
  public BoardUI(LayoutManager layout, Game game, String word) {
      super(layout);
      this.b = new Board();
      this.game = game;
      initComponents(word);
  }
  
  public BoardUI(Game game) {
      this.game = game;
  }
  
  private void initComponents(String word) {
      this.setLayout(new GridLayout(5, 5, 2, 2));
      for (int i = 0; i &lt; 5 * 5; i++) {
          b.getLetters()[i] = new Label();
          b.getLetters()[i].setBackground(Color.WHITE);
          b.getLetters()[i].setForeground(Color.BLACK);
          b.getLetters()[i].setAlignment(Label.CENTER);
          b.getLetters()[i].setFont(new Font("Big", Font.BOLD, 48));
          this.add(b.getLetters()[i]);
      }
  
          for (int i = 0; i &lt; 5; i++) {
              b.getLetters()[i].setText(word.charAt(i) + "");
              b.getLetters()[i].setBackground(Color.BLUE);
          }
      b.setCurrentColumn(0);
      b.setCurrentRow(0);
      }
  
  @Override
  public void keyTyped(KeyEvent e) {
      char typed = e.getKeyChar();
  
      if (Character.isLetter(typed) &amp;&amp; b.getCurrentColumn() &lt; 5) {
          typed = Character.toUpperCase(typed);
          b.getLetters()[b.position(b.getCurrentRow(), b.getCurrentColumn())].setText(typed + "");
          b.getLetters()[b.position(b.getCurrentRow(), b.getCurrentColumn())].setBackground(Color.BLUE);
  
          if (b.getCurrentColumn() == 0) {
              for (int i = 1; i &lt; 5; i++) {
                  b.getLetters()[b.position(b.getCurrentRow(), i)].setText(".");
                  b.getLetters()[b.position(b.getCurrentRow(), i)].setBackground(Color.BLUE);
              }
  
              b.nextColumn(true);
  
              if (b.getCurrentColumn() &lt; 5) {
                  b.getLetters()[b.position(b.getCurrentRow(), b.getCurrentColumn())].setBackground(hoverColor);
              }
  
              if (typed == 8 &amp;&amp; b.getCurrentColumn() &gt;= 0) {
                  this.oneBack();
              }
          }
      }
  }
  
  private void oneBack() {
      if (b.getCurrentColumn() &lt; 5) {
          b.getLetters()[b.position(b.getCurrentRow(), b.getCurrentColumn())].setBackground(Color.BLUE);
          b.nextColumn(false);
          b.getLetters()[b.position(b.getCurrentRow(), b.getCurrentColumn())].setText(".");
          b.getLetters()[b.position(b.getCurrentRow(), b.getCurrentColumn())].setBackground(Color.BLUE);
      }
  }
  
  @Override
  public void keyPressed(KeyEvent e) {
  
  }
  
  @Override
  public void keyReleased(KeyEvent e) {
  
  }
  }
  </code></pre>
  
  <p>Board.java:</p>
  
  <pre><code>import java.awt.*;
  
  public class Board {
  private Reader reader = new Reader();
  private Label[] letters = new Label[5 * 5];
  private String[] words = new String[100];
  private int currentRow, currentColumn;
  
  public Label[] getLetters() {
      return letters;
  }
  
  public String firstWord() {
      return getWord().charAt(0) + "....";
  }
  
  public String getWord() {
      int count = reader.LeesWoordenVanFile(words);
      int x = (int) (Math.random() * 100);
      int gokX = (x % count);
      return words[gokX].toUpperCase();
  }
  
  public int position(int row, int column) {
      return row * 5 + column;
  }
  
  public void nextColumn(boolean next) {
      if (next) {
          currentColumn++;
      } else {
          currentColumn--;
      }
  }
  
  public int getCurrentRow() {
      return currentRow;
  }
  
  public int getCurrentColumn() {
      return currentColumn;
  }
  
  public void setCurrentRow(int currentRow) {
      this.currentRow = currentRow;
  }
  
  public void setCurrentColumn(int currentColumn) {
      this.currentColumn = currentColumn;
  }
  }
  </code></pre>
  
  <p>GUI.java:</p>
  
  <pre><code>import javax.swing.*;
  import java.awt.*;
  
  public class GUI extends JFrame {
  
  private JPanel gamePanel;
  private Game game;
  private Board board = new Board();
  private BoardUI boardUI = new BoardUI(game);
  
  public GUI(String title) throws HeadlessException  {
      super(title);
      game = new Game();
      setupVieuw();
      showFrame();
      this.addKeyListener(boardUI);
  }
  
  public void setupVieuw() {
      getContentPane().removeAll();
      initComponents(board.firstWord());
      layoutComponents();
      this.validate();
  }
  
  public void layoutComponents() {
      getContentPane().add(gamePanel, BorderLayout.CENTER);
  }
  
  private void initComponents(String word) {
      gamePanel = new JPanel(new BorderLayout());
      gamePanel.add(new BoardUI(new BorderLayout(),game, word));
  }
  
  private void showFrame() {
      this.setBounds(50, 50, 800, 800);
      this.setPreferredSize(new Dimension(600, 600));
      this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      this.pack();
      this.setVisible(true);
      this.doLayout();
  }
  }
  </code></pre>