protected void checkAssignability(AnnotatedTypeMirror varType,Tree varTree){
  if (TreeUtils.isExpressionTree(varTree)) {
    AnnotatedTypeMirror rcvType=atypeFactory.getReceiverType((ExpressionTree)varTree);
    if (!isAssignable(varType,rcvType,varTree)) {
      checker.report(Result.failure("assignability.invalid",InternalUtils.symbol(varTree),rcvType),varTree);
    }
  }
}

protected void checkAssignability ( AnnotatedTypeMirror varType , Tree varTree ) { if ( TreeUtils . isExpressionTree ( varTree ) ) { AnnotatedTypeMirror rcvType = atypeFactory . getReceiverType ( ( ExpressionTree ) varTree ) ; if ( ! isAssignable ( varType , rcvType , varTree ) ) { checker . report ( Result . failure ( "assignability.invalid" , InternalUtils . symbol ( varTree ) , rcvType ) , varTree ) ; } } }
tests , for a re - assignment , whether the variable is assignable or not . if not , it emits an assignability . invalid error .
