AVal: an extensible attribute‐oriented programming validator for Java

Abstract

Attribute‐oriented programming (@OP) permits programmers to extend the semantics of a base program by annotating it with attributes defined in an attribute domain‐specific language (AttDSL). In this article, we propose AVal: a Java5 framework for the definition and checking of rules for @OP in Java. We define a set of meta‐annotations to allow the validation of @OP programs, as well as the means to extend these meta‐annotations by using a compile‐time model of the program's source code. AVal is fully integrated into the Eclipse IDE. We show the usefulness of the approach by using examples of its use applied to three AttDSLs: an @OP framework that helps programming Simple API for XML parsers, an @OP extension for the Fractal component model called Fraclet, and the JSR 181 for web services definition. Copyright © 2007 John Wiley & Sons, Ltd.

Unified Compile-Time and Runtime Java Annotation Processing

“…Noguera has a similar approach to Cepa in his tool AVal [23], [24], which is used to validate frameworks that are using annotations. Purpose of this validation is checking, whether the framework uses specific annotations in a correct way.…”

Annotation Framework Validation Using Domain Models

“…To perform the validation of annotation frameworks AVal [13] applies the concept of annotations itself by defining an annotation framework that contains a set of meta-annotations for the domain of annotation constraints validation. These validation meta-annotations are used to augment the definition of the annotation framework under development with meta-data relevant to validating a given constraint.…”

“…In order to ease the specification of constraints, AVal provides a number of annotations that represent commonly used rules. A subset of these annotations, as well as their description is shown in Table 1, for a more complete discussion on AVal's annotations see [13].…”

“…If the expression evaluates to false, an error is raised. Since the constraint checker uses AVal, the errors are presented to the programmer in the same format as Java compiler errors (see [13]). Although the process to validate the constraints of a program starting from the annotation framework, all the way to obtaining the errors may seem long, it is important to note that each of the actors see only a one-step process.…”

“…A Component's name must be unique in the application By default, the name of a component is the simple name of the class on which the Component The previous version of Fraclet (studied in [13]) used AVal and needed six different annotations to perform the same tests we have implemented here with only OCLConstraint. In addition to this, we were able to elegantly specify the default values for the names of the Component and Attribute annotations, which was not addressed in the previous AVal-based version.…”