No compilation error but have problems when running.

Question

Hello all,
After implementing the examples given from the TextComponentJavaDemo in Java Tutorials I tried to get the fonts to change text in the JEditorPane but to no avail.
The problem I am having now is some java.lang.Null.PointerException .
The errors are shown as follows:
Exception in thread "main" java.lang.NullPointerException
at guiClient.createActionTable<guiClient.java :191>
at guiClient.<init> <guiClient.java:52>
at guiClient.main <guiClient.java:308>
Here is the whole code for the syntax but it cannot be compiled:
/* * My GUI Client */
import javax.swing.*;
import javax.swing.text.*;
import java.awt.*;
//for HTML Headers
import javax.swing.text.StyledEditorKit.*;
import javax.swing.text.html.HTMLEditorKit.*;
import javax.swing.text.html.*;
import javax.swing.event.HyperlinkListener;
import javax.swing.event.HyperlinkEvent;
import javax.swing.event.HyperlinkEvent.EventType;
import javax.swing.text.html.HTMLFrameHyperlinkEvent;
import javax.swing.text.*;
//for layout managers
import java.awt.event.*;
//for action and window events
import java.io.*;
import java.net.*;
import java.awt.GraphicsEnvironment;
import java.util.HashMap;
public class guiClient extends JFrame implements ActionListener {
protected static final String textFieldString = "JTextField";
protected static final String loadgraphicString = "LoadGraphic";
protected static final String connectString = "Connect";
static JEditorPane editorPane;
static JPanel layoutPanel = new JPanel(new BorderLayout());
static JPanel controlPanel = new JPanel(new BorderLayout());
static PrintStream out;
static DrawPanel dPanel;
static DrawControls dControls;
static AnimationButtons aControls;
static String userString;
static JTextField userName = new JTextField();
public static JMenuBar menuBar;
private static JButton connectbutton = new JButton("Connect");
static boolean CONNECTFLAG = false;
AbstractDocument doc;
HashMap actions;
//create the gui interface
public guiClient() {
     super("My Client");
//Create a regular text field.
     JTextField textField = new JTextField(10);
     textField.setActionCommand(textFieldString);
     textField.addActionListener(this);
//Create an editor pane.
    createActionTable(editorPane); //From TextComponentDemo
    editorPane = new JEditorPane();
     editorPane.setContentType("text");
     editorPane.setEditable(true);
//set up HTML editor kit
     HTMLDocument m_doc = new HTMLDocument();
     editorPane.setDocument(m_doc);
     HTMLEditorKit hkit = new HTMLEditorKit();
     editorPane.setEditorKit( hkit );
     editorPane.addHyperlinkListener(new HyperListener());
//Create whiteboard
        dPanel = new DrawPanel();
        dControls = new DrawControls(dPanel);
        aControls = new AnimationButtons (dPanel);
        JPanel whiteboard = new JPanel();
        whiteboard.setLayout(new BorderLayout());
        whiteboard.setPreferredSize(new Dimension(300,300));
        whiteboard.add("Center",dPanel);
        whiteboard.add("South",dControls);
       // whiteboard.add("North",aControls);
     JScrollPane editorScrollPane = new JScrollPane(editorPane);
     editorScrollPane.setVerticalScrollBarPolicy( JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
     editorScrollPane.setPreferredSize(new Dimension(250, 145));
     editorScrollPane.setMinimumSize(new Dimension(50, 50));
//     StyledDocument styledDoc = editorPane.getStyledDocument();
//put everything in a panel
     JPanel contentPane = new JPanel();
     contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.Y_AXIS));
//add whiteboard
     contentPane.add(whiteboard);
//add editor box
     contentPane.add(editorScrollPane);
//add spacer
     contentPane.add(Box.createRigidArea(new Dimension(0,5)));
//add textfield
     contentPane.add(textField);
//set up layout pane
     layoutPanel.add(BorderLayout.WEST,new Label("Name: ")); //add a label
     layoutPanel.add(BorderLayout.CENTER, userName ); //add textfield for user names
     layoutPanel.add(BorderLayout.SOUTH, connectbutton);//add dropdown box for fonts
     contentPane.add(layoutPanel);
     contentPane.add(controlPanel);
     contentPane.add(aControls);
//Create the menu bar.
        menuBar = new JMenuBar();
        setJMenuBar(menuBar);
//Build the first menu.
     JMenu menu = new JMenu("File");
     JMenu styleMenu = createStyleMenu();
     menu.setMnemonic(KeyEvent.VK_F);
     menuBar.add(menu);
     menuBar.add(styleMenu);
//a group of JMenuItems
     JMenuItem menuItem = new JMenuItem("Load Graphic", KeyEvent.VK_L);
     menu.add(menuItem);
        menuItem.setActionCommand(loadgraphicString);
     menuItem.addActionListener(this);
        connectbutton.setActionCommand(connectString);
        connectbutton.addActionListener(this);
     setContentPane(contentPane);
protected JMenu createStyleMenu() {
        JMenu menu = new JMenu("Style");
        Action action = new StyledEditorKit.BoldAction();
        action.putValue(Action.NAME, "Bold");
        menu.add(action);
        action = new StyledEditorKit.ItalicAction();
        action.putValue(Action.NAME, "Italic");
        menu.add(action);
        action = new StyledEditorKit.UnderlineAction();
        action.putValue(Action.NAME, "Underline");
        menu.add(action);
        menu.addSeparator();
        menu.add(new StyledEditorKit.FontSizeAction("12", 12));
        menu.add(new StyledEditorKit.FontSizeAction("14", 14));
        menu.add(new StyledEditorKit.FontSizeAction("18", 18));
        menu.addSeparator();
        menu.add(new StyledEditorKit.FontFamilyAction("Serif",
                                                      "Serif"));
        menu.add(new StyledEditorKit.FontFamilyAction("SansSerif",
                                                      "SansSerif"));
        menu.addSeparator();
        menu.add(new StyledEditorKit.ForegroundAction("Red",
                                                      Color.red));
        menu.add(new StyledEditorKit.ForegroundAction("Green",
                                                      Color.green));
        menu.add(new StyledEditorKit.ForegroundAction("Blue",
                                                      Color.blue));
        menu.add(new StyledEditorKit.ForegroundAction("Black",
                                                      Color.black));
        return menu;
     protected SimpleAttributeSet[] initAttributes(int length) {
        //Hard-code some attributes.
        SimpleAttributeSet[] attrs = new SimpleAttributeSet[length];
        attrs[0] = new SimpleAttributeSet();
        StyleConstants.setFontFamily(attrs[0], "SansSerif");
        StyleConstants.setFontSize(attrs[0], 16);
        attrs[1] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setBold(attrs[1], true);
        attrs[2] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setItalic(attrs[2], true);
        attrs[3] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setFontSize(attrs[3], 20);
        attrs[4] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setFontSize(attrs[4], 12);
        attrs[5] = new SimpleAttributeSet(attrs[0]);
        StyleConstants.setForeground(attrs[5], Color.red);
        return attrs;
    private void createActionTable(JTextComponent textComponent) {
        actions = new HashMap();
        Action[] actionsArray = textComponent.getActions();
        for (int i = 0; i < actionsArray.length; i++) {
            Action a = actionsArray;
actions.put(a.getValue(Action.NAME), a);
private Action getActionByName(String name) {
return (Action)(actions.get(name));
static private void insertTheHTML(JEditorPane editor, String html, int location) throws IOException {
     HTMLEditorKit kit = (HTMLEditorKit) editor.getEditorKit();
     Document doc = editor.getDocument();
     StringReader reader = new StringReader(html);
     try {
          kit.read(reader, doc, location);
     } catch (BadLocationException e) {}
//listen for actions being performed and process them
public void actionPerformed(ActionEvent e) {
//if the action is from the textfield (e.g. user hits enter)
     if (e.getActionCommand().equals(textFieldString)) {
          JTextField fromUser = (JTextField)e.getSource();
     if (fromUser != null){
//place user text in editor pane
//send message to server
               if (userName.getText() != null) {
                    userString = userName.getText().trim();
               out.println(userString + ": " + fromUser.getText());
          fromUser.setText("");
     } else if(e.getActionCommand().equals(connectString)) {
          CONNECTFLAG = true;
} else if (e.getActionCommand().equals(loadgraphicString) ) {
          final JFileChooser fc = new JFileChooser();
          int returnVal = fc.showOpenDialog(this);
          if (returnVal == JFileChooser.APPROVE_OPTION) {
               File file = fc.getSelectedFile();
               dPanel.loadImage(file.getAbsolutePath());
               sendImage(file);
//append text to the editor pane and put it at the bottom
public static void appendText(String text) {
     if (text.startsWith("ID ") ) {
          userString = text.substring(3);
     } else if (text.startsWith("DRAW ") ) {
          if (text.regionMatches(5,"LINE",0,4)) {
dPanel.processLine(text);
     }else if (text.regionMatches(5,"POINTS",0,5)) {
     dPanel.processPoint(text);
     } else if (text.startsWith("IMAGE ") ) {
int len = (new Integer( text.substring(6, text.indexOf(",")))).intValue();
//get x and y coordinates
     byte[] data = new byte[ (int)len ];
     int read = 0;
try {
     while (read < len) {
     data = text.getBytes( text.substring(0, len) );
} catch (Exception e) {}
     Image theImage = null;
     theImage = dPanel.getToolkit().createImage(data);
     dPanel.getToolkit().prepareImage(theImage, -1, -1, dPanel);
     while ((dPanel.getToolkit().checkImage(theImage, -1, -1, dPanel) & dPanel.ALLBITS) == 0) {}
          dPanel.drawPicture(0, 0, theImage);
} else {
//set current position in editorPane to the end
          editorPane.setCaretPosition(editorPane.getDocument().getLength());
//put text into the editorPane
          try {
               insertTheHTML(editorPane, text, editorPane.getDocument().getLength());
          } catch (IOException e) {}
} //end of appendText(String)
public void sendImage(File file) {
//find length of file
     long len = file.length();
//read file into byte array
     byte[] byteArray = new byte[(int)len];
     try {
          FileInputStream fstream = new FileInputStream(file);
          if (fstream.read(byteArray) < len) {
//error could not load file
          } else {
          out.println("IMAGE " + len + ",");
               out.write(byteArray, 0, (int)len); //write file to stream
     } catch(Exception e){}
//run the client
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
final guiClient frame = new guiClient();
//Display the window.
frame.pack();
frame.setVisible(true);
public static void main(String[] args) {
     String ipAddr=null, portNr=null;
          if (args.length != 2) {
               System.out.println("USAGE: java guiClient IP_Address port_number");
               System.exit(0);
          } else {
     ipAddr = args[0];
          portNr = args[1];
          JFrame frame = new guiClient();
          frame.addWindowListener(new WindowAdapter() {
               public void windowClosing(WindowEvent e) { System.exit(0); }
          frame.pack();
          frame.setVisible(true);
          while(CONNECTFLAG == false){}
//sames as previous client,
//set up connection and then listen for messages from the Server
          String socketIP = ipAddr;
          int port = Integer.parseInt(portNr);
//the IP address of the machine where the server is running
          Socket theSocket = null;
//communication line to the server
          out = null;
//for message sending
          BufferedReader in = null;
//for message receiving
          try {
          theSocket = new Socket(socketIP, port );
//try to connect
          out = new PrintStream(theSocket.getOutputStream());
               dPanel.out = out;
//for client to send messages
          in = new BufferedReader(new InputStreamReader(theSocket.getInputStream()));
               BufferedReader userIn = new BufferedReader(new InputStreamReader(System.in));
               String fromServer;
               while ((fromServer = in.readLine()) != null) {
               appendText(fromServer);
               if (fromServer.equals("BYE")) {
                    appendText("Connection Closed");
                    break;
          out.close();
//close all streams
          in.close();
          theSocket.close();
//close the socket
     } catch (UnknownHostException e) {
//if the socket cannot be openned
          System.err.println("Cannot find " + socketIP);
          System.exit(1);
          } catch (IOException e) { //if the socket cannot be read or written
          System.err.println("Could not make I/O connection with " + socketIP);
          System.exit(1);
          javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
Can someone tell me what's the problem with the syntax?

Answer 1

For your nullPointerException, you have to create your textPane before calling createActionTable          editorPane = new JEditorPane();
          createActionTable(editorPane); //From TextComponentDemoAlso, I would like to point out the following :
- you're creating your guiClient twice in the main method : at the beginning and at the end through the createAndShowGUI.
- for no apparent reason, all your member fields are declared static.
- naming conventions : class names must start with a capital letter.