People always define Logger in upper case for not having PMD warning
According to SUN code convention only constants should be defined in upper case.
Every thing that you define as static and final doesn’t not become constant, but it should immutable too.
Logger are not immutable like other primitive types e.g number and String, Logger are not constant and they should
not be treated like that.
Therefor it should be defined in lower case.
I know now PMD and other code checker will give warning on this, but i think We should be fix the rule, not code for these type of warning.