The security problem of nested classes

This paper mainly discusses the security problem of OO languages caused by the introduction of the nested class mechanism. Firstly, by analyzing vario us cases concerning about nested classes instances and their owner objects in detail, we illustrate the invalid owner problem arising from the differe nce between the lifetime of nested class instances and their owner objects. Then a solution to solve this problem is presented. Finally, a conclusion is drawn that the nested class mechanism should be suitable for the languag es in which user defined classes are only used to declare dynamically creat ed objects and which have garbage collection support, such as Java, not for the languages in which classes are allowed to declare static objects or lo cal objects and which have no garbage collection support, such as C++.