Panel implements Runnable?

Is it possible to implement Runnable in a Frame panel?
I have an Applet Frame for drawing polylines and I want to add a scrolling text panel at the bottom of the frame.
I have a horizontal text applet already, however, when I try to add it's functionality to the frame's panel I get a nullpointerexception error.
Can anybody help,
thanks Aidan

This is the original applet that I used for scrolling text.
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
public class TextPanel extends Applet implements Runnable
private Thread textthread;
boolean FirstPass;
private String Text;
private int S;
private Color bgC;
private Color textC;
private Color tempC;
private int xPos;
private int yPos;
private int textWidth;
private int aWide;
private int aHigh;
private String fontName;
private Font F;
private Image iBuff;
private Graphics gBuff;
private Image iTheText;
private Graphics gTheText;
private boolean LoadPause;
private int RP;
private int VB;
public TextPanel()
textthread= null;
FirstPass = true;
Text = " Scrolling Text. ";
S = 40;
xPos = 1;
yPos = 0;
textWidth = 0;
aWide = 0;
aHigh = 0;
bgC = new Color(255, 255, 255);
textC = new Color(0, 0, 0);
tempC = textC;
fontName = "TimesRoman";
LoadPause = true;
RP = 1000;
VB = 0;
iBuff = null;
gBuff = null;
public void init()
aWide = 600;
aHigh = 16;
prepMessage();
makeText();
if (iBuff == null)
iBuff = createImage(aWide, aHigh);
gBuff = iBuff.getGraphics();
public void prepMessage()
FontMetrics fontmetrics = null;
F = new Font(fontName, Font.PLAIN, 16);
fontmetrics = getFontMetrics(F);
textWidth = fontmetrics.stringWidth(Text);
int j = fontmetrics.getAscent();
yPos = aHigh - fontmetrics.getMaxDescent() - fontmetrics.getMaxDescent() / 3;
yPos = yPos + VB;
public void makeText()
iTheText = createImage(textWidth, aHigh);
gTheText = iTheText.getGraphics();
gTheText.setColor(bgC);
gTheText.fillRect(0, 0, textWidth, aHigh);
gTheText.setColor(tempC);
gTheText.setFont(F);
if(!FirstPass)
gTheText.drawString(Text, 0, yPos);
public void update(Graphics g)
paint(g);
public void paint(Graphics g)
if(++xPos > textWidth)
xPos = 1;
int i = xPos * -1;
do
if(!FirstPass)
gBuff.drawImage(iTheText, i, 0, this);
if(FirstPass)
gBuff.drawImage(iTheText, 0, 0, this);
i = 0;
i += textWidth;
} while(i < aWide);
g.drawImage(iBuff, 0, 0, this);
public void start()
if(textthread== null)
textthread= new Thread(this);
textthread.start();
public void stop()
if(textthread!= null)
textthread= null;
public void run()
if(FirstPass)
FirstPass = false;
     makeText();
     if (!FirstPass)
     do
try
repaint();
if(LoadPause)
try
TextPanel _tmp = this;
Thread.sleep(RP);
catch(InterruptedException interruptedexception) { }
LoadPause = false;
TextPanel _tmp1 = this;
Thread.sleep(S);
catch(InterruptedException interruptedexception1)
stop();
     }while(true);
     else
     return;
I was hoping to have a class
Where the applet created a frame with e.g. a canvas panel and a textscrolling panel i.e. by changing the init() method to include the following.
public void init()
Frame frame = new Frame("Text scroller");
frame.setSize(600, 100);
Panel panel = new Panel();
panel.setSize(aWide, aHigh);
TextPanel textpanel = new TextPanel();
panel.add(textpanel);
frame.add(panel);
textpanel.start();
frame.setVisible(true);
The text scroller runs in the html page and the frame is empty. is it possible to add the scrolling text to the frame.

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After more debugging it turned out all the exceptions are handled correctly but some how after some time the thread just stops running in the servlet and even after invoking the servlet manually it doesn't start. Now asThread may take arround couple of minutes to finish but I am starting a new run every 1 minute which may lead to several Threads running a one particular time and as the time goes on thread increase also. So wondering if there's any limit on number of Threads to run at one particular time or is the Application Server removing any of these as in the code I don't see anything and no errors in the logs either.
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