java - Calling SwingUtilities.invokeAndWait in a loop -

i trying save .png image of jframe. in jframe, have 2 plot3dpanel objects. because of synchronization fault, left-size frame invisible while saving .png.

therefore, use following code:

try {     swingutilities.invokeandwait(new runnable() {         public void run() {             new visualserializer(p[i], q[i], folder + "c" + i).run();         }     });      serialize(p[i], folder + "p" + i);     serialize(q[i], folder + "p" + i);  } catch(exception e) {     e.printstacktrace(); } 

but now, compile error

cannot refer non-final variable inside inner class defined in different method

however, need filenames different. also, need iterate through array of objects. can prevent error?

one way make final copies of variable needs passed anonymous inner class, instance if i problem:

final int index = i; swingutilities.invokeandwait(new runnable() {     public void run() {         new visualserializer(p[index], q[index], folder + "c" + index).run();     } }); 

another solution use class fields inside of anonymous inner class.