CDOL的封装性研究

Research on encapsulation in CDOL

封装性是面向对象技术的一个重要概念 ,文章首先讨论了封装在面向对象数据库中的意义、所存在的问题及其处理方式。针对演绎的面向对象数据库的要求 ,在约束演绎的对象查询语言 (CDOL )中引入 *计算 ,将面向值和面向对象的特征融合 ,在一定程度上打破封装 。

Encapsulation is an important concept in object oriented technology. This paper discusses the meaning of encapsulation in object oriented database,the existing problems and the treatment methods. The * operator is introduced into constraint deductive object oriented database query language(CDOL) to meet the demand of deductive object oriented database. This operator naturally integrates the value oriented data with the object oriented data,breaking the encapsulation to a certain extent,so the language is made more flexible and more practicable.