A Homogeneous Set-Based Object-Oriented Model

• Main Authors: Kwo, Wen Hwang, 郭文煌
• Other Authors: Daniel J. Buehrer
• Format: Others
• Language: en_US
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/05990086902724675910

碩士 === 國立中正大學 === 資訊工程研究所 === 82 === We present an object-oriented data model which includes an algebra of classes that is closed under the operations of union, intersection, difference, selection, projection, and join. The closure property means that any set expression has a well- defined set of elements with a specific set of required attributes with well-defined domains, and which satisfy a well- defined invariant. Therefore, each class also has a definite set of ISA parent classes, ISA subclasses and inherited slots and methods with well-defined domains. The involving the union, intersection, difference, select, project, and join operators. That is, the set expression is moved into its correct location in the ISA hierarchy, depending on the invariant which is computed for that expression.