How to invoke methods from an other class?

Hello,
I've got the following problem I can't solve:
I have a class that extends JApplet (viewtiff) and another that displays the images (DisplayJAI). Now I have implemented the MouseListener in DisplayJAI and on a right-click it should execute a method located in viewtiff.
If viewtiff would be created by myself with the new operator, this wouldn't be a problem. I just had to write instance_name.method() to invoke it, but in this case I don't know the instance name of my viewtiff class because it gets created by the JApplet I think.
Defining viewtiff static would help, but this isn't possible for the 'main' class in an applet. What can I do now?
Many thanks,
Sebastian Tyler

in the constructor// in ViewApplet:
ViewTIFF vt = new ViewTIFF (this);
// in ViewTIFF:
class ViewTIFF {
private ViewApplet va;
public ViewTIFF (ViewApplet va) {
this.va = va;
void someMethod () {
va.someMethod ();
}>> a setter method// in ViewApplet:ViewTIFF vt = new ViewTIFF ();
vt.setViewApplet (this);
// in ViewTIFF:
class ViewTIFF {
private ViewApplet va;
public void setViewApplet (ViewApplet va) {
this.va = va;
void someMethod () {
va.someMethod ();

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How to invoke methods from an other class?

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