Abstract:

A novel approach to locate the fault for null pointer exception is presented.The approach first computes the static slice guided by the runtime stack,then conducts a null-pointer analysis and aliases analysis on the sliced program and obtains the suspicious statements that throw null-pointer exceptions,and finally generates a fault localization report.The experimental study indicates that,although time spent in runtime stack information collecting and aliases transferring,the proposed approach can narrow the searching space of the problem with runtime stack,and discover the value transfer process with aliases analysis,thereby eliminating false negative and false positive,and improving the effectiveness of fault localization.

Key words: automatic fault localization, null pointer exception, runtime stack, program slicing, alias analysis