Hi,
I'm trying to stop() a sample that's playing in an internal class and i get a null pointer exception. I noticed that the method isPlaying() isn't working either. Method play() is working.

Here is a piece of the code that i'm using these methods:

void press() {
   if(bover && mousePressed) {
     press = true;
     locked = true;
     sound = new Sample(swave);

     if (sound.isPlaying()){
       sound.stop(1);
       sound = null;
       println("stamathse");
     }
     else{
       sound.play();
       println("isPlaying");
     }
         }
   else {
     press = false;
   }
 }

 void release(){
   locked = false;
 }
 void drag(){
   sound.stop(1);
 }

i' ve tried both ess and sonia and it trhows me the same exception. So i guess it's a java problem.
Here is all the inner class:

class SoundBox{
 int posx;
 int posy;
 int nx;
 int ny;
 int rsize;
 int bdifx = 0;
 int bdify = 0;

 boolean otherslocked = false;
 boolean locked = false;
 boolean press;
 SoundBox[] others;
 String sbox;
 Sample sound;
 String swave;
 String fotext;

 SoundBox(int rpx, int rpy, int rs, int difx, int dify, SoundBox[] o, String string, String wavestring){
   nx = rpx;
   ny = rpy;

   bdifx = difx;
   bdify = dify;

   rsize = rs;

   others = o;

   sbox = string;

   swave = wavestring;
 }

 void update()
 {
   posx =nx + bdifx;

   posy =ny + bdify;

   for(int i=0; i<num; i++) {
     if(others[i].locked == true) {
       otherslocked = true;
       break;
     }
     else {
       otherslocked = false;
     }  
   }



   if(press) {

     bdifx = lock(mouseX-rsize/2,0,w-rsize/2);
     bdify = lock(mouseY-rsize/2,0,h-rsize/2);
   }

   if (posy != ny || posx != nx){

     posy = bdify;
     posx = bdifx;
   }

   if(otherslocked == false) {
     over();
     press();
   }


 }

 void over() {
   if(overs (posx, posy, rsize)) {
     bover = true;
   }
   else {
     bover = false;
   }
 }

 void press() {
   if(bover && mousePressed) {
     press = true;
     locked = true;
     sound = new Sample(swave);

     if (sound.isPlaying()){
       sound.stop(1);
       sound = null;
       println("stamathse");
     }
     else{
       sound.play();
       println("isPlaying");
     }
         }
   else {
     press = false;
   }
 }

 void release(){
   locked = false;
 }
 void drag(){
   sound.stop(1);
 }


 void display(){


   if(bover){
     fill(231, 199, 58, 155);

   }
   else{
     fill(245, 228, 47, 155);
   }

   if(press) {
     fill(255, 255, 255, 30);
     stroke(255);
   }
   else{
     stroke(88);
   }
   rect(posx, posy, rsize, rsize);    

   textFont(bfont,10);    
   fill(0);                
   text(sbox, posx, posy, rsize, rsize);  

 }

 int positionx(){
   return posx;
 }

 int positiony(){
   return posy;
 }

 String wavename(){
   return swave;
 }

 void writext(){

   int tx = positionx();
   int ty = positiony();
   //String swn = sBox[i].wavename();

   if(tx >= 0 && tx < w/3 && ty >= 6*(h/10) && ty <= h){
     fotext = swave +"  "+"Lyriki";
     println("---------------------");
   }
   else

       if(tx >= w/3 && tx < 2*(w/3) && ty >= 6*(h/10) && ty <= h){
       fotext = swave +"  "+"Dramatikh";
       println("*********************");

     }
     else

         if(tx >= 2*(w/3) && tx <3* (w/3) && ty >= 6*(h/10) && ty <= h){
         fotext = swave +"  "+"Elafria";
         println("SSSSSSSSSSSSSSSSSSSSSS");
       }
       else {
         fotext = "Den exei kathgoriopoih8ei";
       }

 }

 String pl (){
   return fotext;


 }

}

Yes I know, this code is with the sonia import. When i used ess i didn't use the isPlaying() method...