[JAVA3D]

[Andy Tay]

This is a part of my source code for my project... It is giving me alot of problem and i still couldn't figure how to correct it.. Can any one help me.. It is quite urgent cause my deadline is coming soon...   private Geometry sphereGeometry() {     int f;     int r = 50;   int xc = 100;   int yc = 100;   int zc = 100;   int v;   int bvol;   float rx, ry, rz, spanx, spany, spanz, randx, randy, randz;     bvol = ((xc+r)-(xc-r))*((yc+r)-(yc-r))*((zc+r)-(zc-r));     v = bvol*(60/100);     Point3f[] coordinates;     coordinates = new Point3f[bvol];     for(f = 0; f < v; f++){    randx = 0.0f + (float) (Math.random() * 1.0f);    randy = 0.0f + (float) (Math.random() * 1.0f);    randz = 0.0f + (float) (Math.random() * 1.0f);      spanx = (xc+r)-(xc-r);    spany = (yc+r)-(yc-r);    spanz = (zc+r)-(zc-r);      rx = (randx*spanx)+(xc-r);    ry = (randy*spany)+(yc-r);    rz = (randz*spanz)+(zc-r);      if (((rx-xc)*(rx-xc))+((ry-yc)*(ry-yc))+((rz-zc)*(rz-zc)) <= r) {     coordinates[f].x = rx;     coordinates[f].y = ry;     coordinates[f].z = rz;    }   }     PointArray point = new PointArray(bvol, PointArray.COORDINATES);   point.setCoordinates(0, coordinates);           return point;    } // end of method SphereGeometry in class Bone   When i compile, it doesn't show any problem but when i run, i show me this errors.... I really hope that anyone out that can help me with this problem thanks....   java.lang.NullPointerException             at javax.media.j3d.GeometryArrayRetained.setCoordinates<CompiledCode>             at javax.media.j3d.GeometryArray.setCoordinates<GeometryArray.java:333>             at FinalProject$Bone.sphereGeometry<Compiled Code>             at FinalProject$Bone.<init><FinalProject.java:27>             at FinalProject.createSceneGraph<FinalProject.java:114>             at FinalProject.<init><FinalProject.java:142>             at java.lang.Class.newInstance0<Native Method>             at java.lang.Class.newInstance<Class.java:239>             at sun.applet.AppletPanel.createApplet<AppletPanel.java:532>             at sun.applet.AppletPanel.runLoader<AppletPanel.java:468>             at sun.applet.AppletPanel.run<Compiled Code>             at java.lang.Thread.run<Thread.java:479> Andy