[aspectj-dev] is there a algorithm to compute whether two different poin

[Sandy Zhang <nudt.zhangxian@xxxxxxxxx>]

Hi guys, is there a algorithm to compute whether two different pointcut expressions can share a join point ?

For example, we know these following two pointcut expressions may share a join point.

call( Object java.util.Iterator.*(..) );

call( * java.util.Iterator.next(..) );

 

While these two pointcut expressions definitely won’t share a join point

call( boolean java.util.Iterator.hasNext(..) )

call(Object java.util.Iterator.next())

 

It first seems that the unification algorithm used in prolog can resolve this problem. But the cflow operator changes this as the cflow( call(boolean java.util.Iterator.hasNext(..)) ) and cflow( call( boolean java.util.Iterator.hasNext(..) ) ) maybe share a join point. If we drop the cflow operator, can the unification solve this issue?

 

Maybe this thing seems meaningless to aspectj as the compiler only compiles concrete code. And it is easy to find a shared join point in concrete code. But it maybe a good hint to notify that the user writes a wrong pointcut as it does not select any join point no matter what the code is. For example, the pointcut:

call( boolean java.util.Iterator.hasNext(..) ) && call(Object java.util.Iterator.next()).

 

If we cannot find an algorithm to resolve this problem given the complexity of pointcut, is there a subset of pointcut operators which we can handle?

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Best regards,
 
Xian Zhang