Contributing Factors to Pointcut Fragility

Pointcut fragility is a well-documented problem of AspectOriented Programming with changes to the base-code causing join points to incorrectly fall in or out of scope. In order to combat this problem a tool was developed that provides mechanical assistance to pointcut maintenance. This tool relied on the deep structural commonalities between program elements to detect when pointcut fragility occurs. During the assessment of this tool a number of common practices were uncovered that were employed both in the aspect and basecode that contributed to or prevented pointcut fragility. This paper documents the practices uncovered and describes how they can affect pointcut fragility and design stability in general.