Log warning for usage of argNames attribute in AspectJ annotations

[sbrannen]

Since the introduction of the java.lang.reflect.Parameter API in Java 8, the argNames attributes in AspectJ annotations (such as @Before, @Around, etc.) are no longer necessary.

Instead, the Spring team suggests that code be compiled with the javac -parameters flag to make the parameter names available in the compiled byte code.

In light of that recommendation, we should log a warning any time we detect an explicit argNames attribute declaration in an AspectJ annotation.

[sbrannen]

Related Issues

• @AspectJ argument name resolution algorithm is outdated in reference manual #30026

[sbrannen]

Since argNames attributes are checked first in the ParameterNameDiscover chain (technically before the chain), using argNames can avoid potentially more costly operations in the chain.

In light of that we have decided not to log a warning and instead to recommend the use of -parameters as can be seen in the updated Determining Argument Names and Explicit Argument Names sections of the reference manual.