Hey, I met a problem while I want to run the applet of prcessing thing in my normal java application.
So here is the definition of my processing part:


import processing.core.*;
import wordcram.*;

public class CasWordCram extends PApplet {
    /**
     *
     */
    WordCram words = new WordCram(this);
    @Override
    public void setup() {
        System.out.println("hello++++++++++&&&&&&&****************");
        this.size(500, 400);
        this.background(255);
        this.words.fromWebPage("http://en.wikipedia.org/wiki/Word_cloud");
        this.words.drawAll();
        this.save("test");
    }
}
//So the thing above is running perfectly and I can get the applet window which is fine. (ONLY RUN IT AS A JAVA APPLET INDEPENDENTLY).

public void finishProcessing() {
 
        CasWordCram wordcram = new CasWordCram();
        wordcram.setup(); 
    }
//So this function above is defined in a normal java application. It's under one class. And I built the wordcram class from the defined class above.

 But after compiling it as JAVA APPLICATION. it shows this error:

Exception in thread "main" java.lang.NullPointerException
    at processing.core.PApplet.size(Unknown Source)
    at processing.core.PApplet.size(Unknown Source)
    at de.fhg.iais.kd.tm.quote.casAnnotation.CasWordCram.setup(CasWordCram.java:21)


Can somebody help me with this? I got stuck by this for hours......Thank you for your patient reading~~