// get the listener field for the stack
methodAdapter.getField(typeBeingWoven, LISTENER_FIELD, LISTENER_TYPE);
// check if the listener field was non-null and goto return true if it was
methodAdapter.ifNonNull(returnTrueLabel);
// return false if we haven't jumped anywhere
methodAdapter.push(false);
methodAdapter.returnValue();
// mark the returnTrueLable
methodAdapter.mark(returnTrueLabel);
methodAdapter.push(true);
methodAdapter.returnValue();