Nierstrasz, O. A Survey of Object-Oriented Concepts. In Kim, W., Lochovsky F.H. (eds.) Object-Oriented Concepts, Databases, and Applications. ACM Press (1989).  Home/Search   Document Details and Download   Summary   Related Articles   Check

....Cobol suffered from numerous problems that limited maintainability and large scale development. From these were born structured languages like Pascal, Algol and Modula which attempted to organize programs into more modular structures. Object orientation combines strict modularity with inheritance [Nie89] to facilitate reuse and maximize extensibility, maintainability, and portability. There are four features supported by object oriented languages: encapsulation, data abstraction, inheritance, and polymorphism. Combined, these provide a powerful mechanism for design reuse. Each of these is ....

....maintainability, and portability. There are four features supported by object oriented languages: encapsulation, data abstraction, inheritance, and polymorphism. Combined, these provide a powerful mechanism for design reuse. Each of these is described in detail below, with material drawn from [Nie89] and [Weg87] 2.1.1 Encapsulation Decomposing programs into procedures increases code readability and maintainability, yet aside from simple functional procedures each procedure call will modify state information external to the procedure. This requires either numerous parameters to each ....

Oscar Nierstrasz. A Survey of Object-Oriented Concepts. In Won Kim and Frederick H. Lochovsky, editors, Object-Oriented Concepts, Databases, and Applications, pages 3--22. Addison-Wesley, Reading, Massachusetts, 1989.

....to ensure consistency. For efficiency reasons, fully concurrent objects are usually implemented as passive objects (standard objects without any activity) without any synchronization, and they are replicated on every processor [26] Other models distinguish between data and behavioral objects [84]. Thus, one type of objects is used to structure shared memory as a collection of passive objects , while a process is considered a special kind of active process object . The actions on passive shared objects are performed according to their declared interface. The active objects access the ....

....to integrating objects and concurrency (see [82, 112] for complete surveys) First, we briefly review the main concepts. Then we present the approaches to high performance applications in more detail. Pure object oriented concurrent languages satisfy the requirements for objectorientation [84], such as inheritance. In languages like [3, 114] an object can accept concurrent requests through messages. These models support intra object concurrency. In such a model an object is shared or visible to concurrent processes. In a distributedmemory environment this translates into support for ....

Oscar Nierstrasz. A survey of object-oriented concepts. In W. Kim and F. Lochovsk, editors, Object-Oriented Concepts, Databases and Applications, pages 3--21. ACM Press and Addison Wesley, 1989.

....that is generally agreed to be an indispensable (sine qua non) characteristic of object oriented languages. Some researchers even consider encapsulation to be the fundamental object oriented concept and that all other object oriented mechanisms and approaches exploit encapsulation to various ends ([9]) There also seems to be general agreement on the fact that encapsulation and sharing are incompatible: sharing tends to violate encapsulation while encapsulation tends to prevent sharing. This paper reviews the relationship of encapsulation and sharing and proposes an enhanced notion of ....

O. Nierstrasz: "A Survey of Object-Oriented Concepts". In Object-Oriented Concepts, Databases and Applications, W. Kim; F. Lochovsky (Eds.), pp. 3-21. Reading, Mass., ACM Press and Addison-Wesley, 1989.

....with computational power. In this model, the object is an autonomous entity which interacts with another objects in the system. The mechanism used for the communication is the message passing. 3. 3 Comparison The main advantage obtained by the adoption of an active object model is homogeneity [7]. The active model offers a powerful abstraction of the object that fits well with our goals. These objects will be homogeneous, that is, all the objects will have the same properties. Besides, the objects will be selfcontained; every object must contain its own private activities. Because ....

O. Nierstrasz. A Survey of Object-Oriented Concepts. In OO Concepts, Databases and Applications. Ed. W. Kim and F. Lochovsky. ACM Press and Addison-Wesley, 1989.

....and straightforward correlations with real world concepts. Many authors side step the quality issue by describing the general elements of the object oriented paradigm, including identity, classification, abstraction, and encapsulation, but without giving any quality 1 assessment criterion [2, 8, 10, 11, 12, 15]. Although informal descriptions of these elements provide a framework for evaluating quality, they do not provide the means. Other approaches focus on class definitions with principles like sufficiency, completeness, and primitiveness [1] These principles are useful for verifying ....

Nierstrasz, O. M. "A Survey of Object-oriented Concepts," In Object-oriented Concepts, Databases, and Applications, W. Kim, F. H. Lochovsky, eds., 1989, pp. 3-22.

....understanding the special problems involved in the implementation of our integrated model. We assume that the reader is familiar with the standard notions of class, instance, and classbased inheritance that are common in most of today s object oriented languages and systems ( Wegn89] Snyd91] Nier89] GR89] Stro91] Meye92] We also assume that inheritance is based on overriding [CoPa89] rather than extension ( BrCo90] MMN93] In our model, as in many other existing systems, objects are instances of classes, classes may inherit from each other, and all variables, parameters and ....

Oscar Nierstrasz: "A Survey of Object-Oriented Concepts". In [KL89], pp. 3-22.

.... literature, denoting consultance ( LTP86] GSR94] or variants of consultance ( Stro87] WJS94] ABGO93] Also the term object based inheritance is often used in literature in a more restricted sense, mostly denoting static forwarding relationships between objects, e.g. static delegation in [Nier89 and static consultance in [HaNg87] gk cs.uni bonn.de IAI TR 96 11 5 forwarded to persJohn. When the method for currentPhone# is found in persJohn, its self will be bound to the message receiver, empJohn, if delegation is used, and to the method holder, persJohn, if consultance is used. Thus, ....

O. Nierstrasz: "A Survey of Object-Oriented Concepts". In [KiLo89], pp. 3-22.

....into the final software system. The method outlines a development strategy oriented to objects and to reusability from the early phases. In particular, specifications are formalized considering the possibility of reusing them, and to build automatic tools supporting object oriented analysis [25]. Among the tools comprising the ITHACA Development Information System are: RECAST (Requirements Composition And Specification Tool) supports the composition, via guided selection [26] 13] of requirements specified in the object oriented specification model, called Functionality in the Objects ....

....Model (F ORM) 28] represents the formal basis for requirements specification. Application requirements are represented as classes, objects are created as class instances, and messages are used to access the services provided by objects. The concept of role extends the object oriented paradigm [25] to model the different behaviours an object can have during its life time [28] thus an object can send and receive different messages at different stages of its evolution. The role dynamics is represented via state transition diagrams; role data are described as a set of properties. In the ....

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O. Nierstrasz, "A Survey of Object-Oriented Concepts", in "Object-Oriented Concepts, Databases and Applications " ed. W. Kim and F. Lochovsky, Addison-Wesley/ACM Press, 1989

....the past years. While knowledge representation formalisms such as terminological or description logics [32, 23] feature clear and elegant semantics and provide powerful subsumption and classification based inference algorithms operating on purely declarative databases, object oriented programming [25, 30, 29] has its strengths in flexible control structures utilizing message passing and in software engineering issues like modularization and reuse. Several attempts at combining OCKR with programming facilities have been made, but the procedural aspects of knowledge representation systems are often only ....

O. Nierstrasz. A survey of object-oriented concepts. In W. Kim and F. Lochovsky, editors, ObjectOriented Concepts, Databases and Applications, pages 3--21. Addison-Wesley, 1989.

.... coming down to low level data modeling from higher level conceptual modeling [7] However paradigms for modeling the dynamics of object oriented databases are unclear regarding whether services provided by objects, are part of the object database or are explicitly outside the database [20]. In a similar vein, the principles which concern information systems design, as contended by Alter [3] is said to boil down to management of the following three issues: ffl The information content ffl The organization of the information ffl Mechanisms to enable users obtain whatever ....

Oscar Nierstrasz. A Survey of Object-Oriented Concepts. In W. Kim, F. H. Lochovsky (Eds.) Object-Oriented Concepts, Databases, and Applications, ACM Press 1989.

....both the development time and the maintenance cost, and, at the same time, simplify the creation of large and complex software systems. The explosion of interest in object oriented design in the 80s led to a proliferation of definitions and interpretations of this much used and much abused term [46]. In 1982, Rentsch described the situation in [49] What is object oriented programming My guess is that object oriented programming will be in the 1980 s what structured programming was in the 1970 s. Everyone will be in favor of it. Every manufacturer will promote his products as supporting it. ....

O. Nierstrasz. A Survey of Object Oriented Concepts. Object-Oriented Concepts, Databases, and Applications, pages 3--21, 1989.

....the definitions and restrictions on the use of inheritance vary considerably. Most systems use it for specialization, while some also use it for aggregation. Some languages like C are quite liberal with inheritance, allowing it for the purpose of code reusability in case of partial inheritance [Nier89]. To make our discussion of inheritance in Active KDL more precise, it is imperative to isolate two aspects of inheritance: the intensional aspect and the extensional aspect. The intensional state of the database specifies the type structure for all the types (or classes) defined for the database. ....

Nierstrasz, O., "A Survey of Object-Oriented Concepts," Object-Oriented Concepts, Databases, and Applications, W. Kim and F.H. Lochovsky (Eds.), Addison-Wesley, Reading, MA (1989).

.... of models, the X3 SPARC DBSSG OODBTG report [FKMT91] defines an open object model architecture and recommends some standards for object data management (ODM) and several other classifications of object oriented concepts have also appeared [CW85, SB85, AC86, KC86, Ull87, Weg87, Kin89, Mai89, Nie89, Str90] These papers serve as useful guidelines to measure the objectness of various models. The formal model proposed here draws from all these reports and incorporates several of their core concepts. Several other models that have also influenced our design are discussed below. Kent ....

O. Nierstrasz. A Survey of Object-Oriented Concepts. In W. Kim and F.H. Lochovsky, editors, Object-Oriented Concepts, Databases, and Applications. Addison Wesley, 1989.

....respect to requests traffic, when requesting for the objects. Keywords: communication overhead, complex objects, databases, distributed environment, multimedia, object partitioning. 1 Introduction The advent of multimedia information processing has pushed the object oriented programming paradigm [1, 2] into becoming one of the most popular techniques for application and system development. Multimedia information processing involves the integrated handling of myriad of different data types derived from different media. As a result of the heterogeneity of the data types and the necessity to ....

Oscar Nierstrasz, "A Survey of ObjectOriented Concepts," in Object-Oriented Concepts, Databases, and Applications, AddisonWesley, Reading, MA, 1989, pp. 3-22.

....Database Systems Object oriented database systems try to blend the object oriented paradigm with database technology. We therefore shortly introduce both areas and then present object oriented database systems. 2. 1 Object Orientation The general characteristics of the object oriented paradigm [24] are objects and object identity, classes, and inheritance specialization. They should apply to all models, systems, methods, etc. that claim the label of being object oriented. An object is a concept to represent a real or virtual entity; each object has a state and exhibits a certain kind of ....

O. Nierstrasz. A Survey of Object-Oriented Concepts. In W. Kim and F.H. Lochovsky, editors, Object-Oriented Concepts, Databases, and Applications. ACM Press, New York, 1989.

....and optimal allocation of objects. Keywords: bipartite matching, communication overhead, complex objects, distributed systems, efficient allocation, multimedia, object partitioning. 1 Introduction The advent of multimedia information processing has pushed the objectoriented programming paradigm [1, 2] into becoming one of the most popular techniques for application and system development. Multimedia information processing involves the integrated handling of myriad of different data types derived from different media. As a result of the heterogeneity of the data types and the necessity to ....

Oscar Nierstrasz, A Survey of Object-Oriented Concepts, ObjectOriented Concepts, Databases, and Applications, pp. 3-22, AddisonWesley, Reading, MA, 1989.

....provide mechanisms for sharing among objects. Two types of sharing are possible: sharing of implementation and sharing of behavior. Behavioral sharing is what we called subtype supertype relationship above. It is important to differentiate this from implementation sharing. As noted by Nierstrasz [Nie89] many of the problems with inheritance arise from the discrepancy between these two notions. He goes further and associates subtyping with types, and inheritance with classes. This follows from the model that he describes where a type is defined as an abstract specification of the behavior ....

O. Nierstrasz. A survey of object-oriented concepts. In W. Kim and F.H. Lochovshy, editors, Object-Oriented Concepts, Databases, and Applications, pages 3--21. Addison Wesley, 1989.

.... classifies and describes the behavior shared by a set of objects[GR83, Str86] Inheritance allows classes to share structural and behavioral descriptions and supports hierarchies of classes[Weg87] Polymorphism allows a particular operation to be applied to objects of various types[Dig86, Nie89] To demonstrate the framework presented in this thesis, I have developed a portable, extensible file system prototype that includes a hierarchy of abstract and concrete file system classes. Besides demonstrating the characteristics of the framework, the prototype serves as the persistent ....

....code sharing, polymorphism, and design sharing. 2.2. 1 Data Encapsulation An object is a software entity that consists of a set of state data and a set of operations on the data[Weg87, Rus91] Objects support data encapsulation by enforcing the use of operations to effect all state changes[Dig86, Nie89] Data encapsulation helps software designers decompose systems into objects by insulating other objects from changes in the structure of the state data. In Smalltalk[GR83] invoking an operation is called sending a message to an object, and the code invoked in response to a message is called a ....

[Article contains additional citation context not shown here]

Oscar Nierstrasz. A Survey of Object-Oriented Concepts. In Won Kim and Frederick H. Lochovsky, editors, Object-Oriented Concepts, Databases, and Applications, pages 3--22. Addison-Wesley, Reading, Massachusetts, 1989.

....We can view the fundamental idea behind the object oriented approach as that of encapsulation: object oriented languages and systems exploit encapsulation in various ways in an attempt to enhance productivity through, for example, reusability mechanisms such as class inheritance. See [Nierstrasz 1988] in this book for an elaboration of this view. The importance of object oriented techniques for software engineering has long been established: encapsulation has been successfully used by programmers ever since macros and subroutines were invented. Encapsulation is important not only for the ....

O.M. Nierstrasz, "A Survey of Object-Oriented Concepts", in ObjectOriented Concepts, Applications and Databases, ed. W. Kim and F. Lochovsky, AddisonWesley, 1988.

....methods) are hidden from other objects. Interaction with objects is through a well defined interface, illustrated by the paradigm of communication via message passing. Object independence can be viewed as fundamental to all object oriented concepts, including, for example, all forms of inheritance [Nierstrasz 1988]. We depict object independence as a boundary around objects, as in figure 1. Database systems, on the other hand, emphasize data independence by separating the world into two independent parts, namely the data and the applications operating on them. The independence boundary is between the ....

O.M. Nierstrasz, "A Survey of Object-Oriented Concepts," in Object-Oriented Concepts, Applications and Databases, ed. W. Kim and F. Lochovsky, Addison-Wesley, 1988, (to appear).

....is straightforward; single inheritance is a 1 n relationship between classes while an m n relationship is needed for multiple inheritance. An interesting question is to what extent the software information system need model the semantics of inheritance. There are many varieties of inheritance [25][39] To take one example, object oriented programming languages differ on whether the instance variables of a superclass are visible to Figure 2 Alternative Views method 2 method 1 Class X private public method 2 method 1 Class X method 2 method 1 implementation 2 implementation 9 Class ....

Nierstrasz, O.M. A Survey of Object-Oriented Concepts. In Object-Oriented Concepts, Databases and Applications, (Ed. W. Kim and F. Lochovsky) Addison-Wesley/ACM Press, 1989, 3-21.

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Nierstrasz, O. A Survey of Object-Oriented Concepts. In Kim, W., Lochovsky F.H. (eds.) Object-Oriented Concepts, Databases, and Applications. ACM Press (1989).

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Nierstrasz, O. - 1989. A survey of object-oriented concepts. Object-Oriented Concepts, Databases and Applications, pp. 3-21, ACM Press and Addison Wesley.

No context found.

Nierstrasz, O. - 1989. A survey of object-oriented concepts. Object-Oriented Concepts, Databases and Applications, pp. 3-21, ACM Press and Addison Wesley.

No context found.

Nierstrasz O.: A Survey of Object-Oriented Concepts. In: Object-Oriented Concepts, Databases and Applications. W. Kim and F. Lochovsky (Eds.) ACM Press and AddisonWesley, pp. 3-21, 1989.

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