Object constraint language formal060501 object management. The object constraint language ocl, which forms part of the uml set of modeling notations, is a precise, textual language for expressing constraints that cannot be shown diagrammatically in uml. He is an active member of the unified modeling language uml revision task force, which defined the revisions in the uml 2. Overall, ocl support is currently very limited in ea. This site is like a library, you could find million book here by using search box in the header. The ocl is a standard query language, which is part of the. Ocl object constraint language masarykova univerzita. Ini tia lly, ocl was merely a formal specification language extension for uml. It is a facility provided within the java programming language to test the correctness or assumptions made by your program.
The object constraint language ocl is a declarative language for describing rules that apply to unified modeling language uml models developed at ibm. Boolean returns true if the tested object is exactly the same type as t. The object constraint language ocl appeared as an effort to overcome the limitations of uml when it comes to precisely specifying detailed aspects of a system design. Getting your models ready for mda by jos warmer and anneke kleppe jos was one of the main creators of the ocl. Object constraint language ocl pure expression language. The object constraint language second edition written by anneke kleppe and jos warmer, explains in no time, how to complete your platform independent models, with business and query language. Syntax constructs enabling to navigate through object links. Graphical model not enough for a precise and unambiguous speci. The object constraint lang uage ocl is a declar ative lan guage describing rules applying to unified m odeling l anguage uml models developed at ibm and is now part of the uml standard. Ocl as specification language for object constraints.
The object constraint language, second edition, utilizes a case study to show how to exercise these compact but powerful expressions for maximum effect. To specify invariants on classes and types in the class model to specify type invariants for stereotypes to describe pre and post conditions on operations and methods to describe guards as a navigation language to specify constraints on operations. Introduction to the object constraint language tutorial. Previously he was a member of the uml core team, where he was responsible for the development of the object constraint language ocl. Object constraint language ocl ocl is a formal language used to describe expressions on uml models. A brief guide to the standard object modeling language utility and constraint function machine learning constraint object base programming vs object oriented programming calling all foreign language teachers computerassisted language. Ocl was first developed in 1995 inside ibm as an evolution of an expression language in the syntropy method 26. Fakultat informatik, institut smt, lehrstuhl softwaretechnologie. All of the power of logic and discrete mathematics. These features all together form the complete uml2.
Founded in 1989, omg standards are driven by vendors, endusers, academic institutions and government agencies. The object constraint language ocl provides a formal. The object constraint language ocl started as a complement of the uml notation with the goal to overcome the limitations of uml and in general, any graphical notation in terms of precisely specifying detailed aspects of a system design. The object constraint language ocl started as a com. The object constraint language is a declarative language for describing rules that apply to unified modeling language models developed at ibm.
Object constraint language what is object constraint language. A constraint invariant is a boolean ocl expression evaluates to truefalse. Overview this document introduces and defines the object constraint language ocl, a formal language to express side effectfree constraints. Object constraint language ocl general and reference. Precise modeling with uml addisonwesley object technology series warmer, jos b. Successful software developers have long recognized that proper modeling is a key element to the development process that leads to creating robust software. For example, constraints within operation specifications pre and postconditions.
Constraint that must be always met by all instances of the class. Object constraint language inria book pdf free download link book now. This book is a practical guide to ocl for software architects, designers, and developers. Ocl a formal specification language extension to uml. The object constraint language ocl started as a complement of the uml notation with the goal to overcome the limitations of uml and in general, any. On the evolution of ocl for capturing structural constraints in modelling languages, lecture notes in computer science, 2009, volume 51152009, 204218.
The object constraint language ocl is a language that enables one to describe expressions and constraints on objectoriented models and other object modelling artefacts. They also specify queries over objects described in a model. The ocl is a standard query language, which is part of the unified modelling language uml set by the object. Object constraint language free ebook download as pdf file. Object constraint language ocl cheat sheet ocl syntax. Contracts in the object constraint language part of uml contracts in ordinary life, a.
If the object is not a descendant of t, the operation is undefined. This book is essential reading for anyone intending to adopt mda technology. The object constraint language ocl is a declarative language describing rules applying to unified modeling language uml models developed at ibm and is now part of the uml standard. Ocl expressions typically specify invariant conditions that must hold for the system being modeled. Object constraint language the object constraint language getting your models ready for mda uml distilled. Copies of specifications, available in postscript and pdf format, may be. Introduction the object constraint language the ocl is used to specify constraints on objects in the uml. Boolean returns true if the tested object is exactly the same type or a subtype of t. Dec, 2015 the object constraint language is a declarative language for describing rules that apply to unified modeling language models developed at ibm and now part of the uml standard. Builtin object properties ocl provides a set of properties on all objects in a system. The object constraint language ocl started as a com plement of the. The object constraint language ocl started as a complement of the uml notation with the goal to overcome the limitations of.
Object constraint language by weijun du what is object constraint language. The object constraint language ocl started as a complement of the uml notation with the goal to overcome the limitations of uml and in general, any graphical notation in terms of precisely. Object constraint modelbased assertion dldf fllwarmer and kleppe define a constraint as follows. Object constraint language ocl is a standard language defined by object management group for specifying constraints on models.
Object constraint language object management group. Ocl object constraint language, joaopascoalfaria, 06 january 2008 9 what is the ocl. Since its introduction as part of unified modeling language, ocl has received significant attention by researchers with works in the literature ranging from temporal extensions of ocl to automated test generation by. The object constraint language ocl started as a com plement of the uml notation with the goal to overcome the limitations of.
Sql is an ansi american national standards institute standard language, but there are many different versions of the sql language. Notes in computer science, 1999, volume 17431999, 793. The parser also seems to allow expressions that are not correct. Alloy, a specification language inspired by z notation and implementing the principles of object constraint language ocl.
The object constraint language ocl is a language that enables one to describe expressions and constraints on object oriented models and other object modelling artefacts. The object constraint language ocl appeared as an e. For the past decade, the object constraint language has offered a more precise but not very popular means of expressing a software design more precise than even the unified modeling language. Constraint language an overview sciencedirect topics. Praise for the object constraint language, second edition mda promises a revolution in the way we develop software. Feb 23, 2015 ocl object constraint language uml am beispiel eines buchungssystems fur ausfluge duration.
The book begins with the ideas behind ocl, that it must model constraints as simply as possible. The object constraint language shows that with simple, elegant ocl statements, a uml design can be made more logically robust and easy to understand. This paper reflects on a number of aspects of the syntax and semantics of the ocl, and makes proposals for clarification or extension. Object constraint language ocl object constraint language. Designed to be used in a postcondition for an operation, it returns true if the object being tested was created as a result of executing the operation. The object constraint language second edition, getting. Ocl is a typed language, so that each ocl expression has a type. Initially, ocl was merely a formal specification language extension for uml.
The context objects may be denoted within the expression using the keyword self. Every constraint is bound to a specific type class, association class, interface in the uml model its context. This specification defines the object constraint language ocl, version 2. The object constraint language the ocl is used to specify constraints on objects in the uml. On formalizing the uml object constraint language ocl pdf mark richters and marin gogolla this paper presents a formal semantics for the object constraint language ocl which is part of the unified modeling language uml an emerging standard language and notation for objectoriented analysis and design. A constraint is a restriction on one or more values a constraint is a restriction on one or more values of part of an objectoriented model or system. Constraint that must be always true beforeafter the execution of the operation as a navigation language. Parts of the syntax seem to have been influenced by smalltalk. This newly updated edition explains why ocl is critical to mdaand why uml alone is not enough introduces an sqllike syntax to ocl defines the new language constructs of ocl 2. Within the last 20 years, the object constraint language ocl 1 has become a widely adopted constraint language used in the context of the uni ed modeling language uml 2 as well as transformation languages like query view ransformationt qvt 3, and other domainspeci c modeling languages. The object constraint language ocl is a formal language used to describe constraints and query expressions in uml models ocl is a pure specification language.
A let expression is both high precedence and low precedence. These predefined value types are independent of any object model and part of the definition of ocl. Stuart kent, andy evans and bernhard rumpe, uml semantics faq, object oriented technology ecoop99 workshop reader, lecture nstuart kent, andy evans et. View object constraint language research papers on academia. All books are in clear copy here, and all files are secure so dont worry about it. But the basic concept remains same as the earlier version. Object constraint language article about object constraint. The object constraint language is a precise text language that provides constraint and object query expressions on an object oriented model that cannot otherwise be expressed by diagrammatic notation. Object constraint language research papers academia. About the object constraint language specification version 2. Copies of specifications, available in postscript and pdf format, may be obtained.