{"id":533,"date":"2014-01-09T19:32:27","date_gmt":"2014-01-09T18:32:27","guid":{"rendered":"http:\/\/blog.ansuz.nl\/?p=533"},"modified":"2014-01-09T19:32:27","modified_gmt":"2014-01-09T18:32:27","slug":"privileged-aspects","status":"publish","type":"post","link":"http:\/\/blog.ansuz.nl\/index.php\/2014\/01\/09\/privileged-aspects\/","title":{"rendered":"Privileged Aspects"},"content":{"rendered":"

When you are using Aspect-Oriented Programming<\/a> with AspectJ<\/a> and you want to get around Java restrictions in your Aspect, you can declare the Aspect “privileged<\/em>“.<\/p>\n

Say you perform some logging from your Aspect, but the member you want to access has no (public) accessor method. You could create a public getter method and use that. Better would be to make the Aspect privileged so it can access the member even though it is declared private. This scenario is demonstrated in the snippets below.<\/p>\n

Given the following class “Foo”.<\/p>\n

\n\n\t\t
\n\n\t\t
\n\t\t\t\t\t\t< View plain text<\/span> ><\/a>\n\t\t\t\t\t<\/div>\n\n\t\t
java<\/div>\n\n\t\t\n\t\t
\n\n\t<\/div>\n\t\n\t
\n\t\t
  1. ppublic class<\/span> Foo {<\/span><\/div><\/li>\n
  2.     private<\/span> String<\/span> bar;<\/span><\/div><\/li>\n
  3.  <\/div><\/li>\n
  4.     private<\/span> void<\/span> doSomething(<\/span>)<\/span> {<\/span><\/div><\/li>\n
  5.         bar =<\/span> "bar"<\/span>;<\/span><\/div><\/li>\n
  6.     }<\/span><\/div><\/li>\n
  7. }<\/span><\/div><\/li>\n<\/ol>\t<\/div>\n\n<\/div>\n\n

    The Aspect would look something like this.<\/p>\n

    \n\n\t\t
    \n\n\t\t
    \n\t\t\t\t\t\t< View plain text<\/span> ><\/a>\n\t\t\t\t\t<\/div>\n\n\t\t
    java<\/div>\n\n\t\t\n\t\t
    \n\n\t<\/div>\n\t\n\t
    \n\t\t
    1. public<\/span> privileged aspect FooLogging {<\/span><\/div><\/li>\n
    2.     protected<\/span> pointcut myClass(<\/span>)<\/span>:<\/span> within(<\/span>Foo)<\/span>;<\/span><\/div><\/li>\n
    3.     private<\/span> pointcut doSomethingMethod(<\/span>)<\/span>:<\/span> myClass(<\/span>)<\/span><\/div><\/li>\n
    4.             &&<\/span> execution(<\/span>doSomething(<\/span>)<\/span>)<\/span>;<\/span><\/div><\/li>\n
    5.  <\/div><\/li>\n
    6.     after(<\/span>)<\/span>:<\/span> doSomethingMethod(<\/span>)<\/span> {<\/span><\/div><\/li>\n
    7.         String<\/span> value =<\/span> (<\/span>(<\/span>Foo)<\/span> (<\/span>thisJoinPoint.getThis<\/span>(<\/span>)<\/span>)<\/span>)<\/span>.bar<\/span>;<\/span><\/div><\/li>\n
    8.         \/\/ Logging goes here.<\/span><\/div><\/li>\n
    9.     }<\/span><\/div><\/li>\n
    10. }<\/span><\/div><\/li>\n<\/ol>\t<\/div>\n\n<\/div>\n\n

      There is one limitation to privileged Aspects though:<\/p>\n

      Privileged aspects are not supported by the annotation style.<\/p><\/blockquote>\n

      See “Aspect Declarations<\/a>” in “Chapter 9. An Annotation Based Development Style<\/em>” of the “The AspectJ 5 Dev Kit Developer’s Notebook<\/a>“.<\/p>\n","protected":false},"excerpt":{"rendered":"

      When you are using Aspect-Oriented Programming with AspectJ and you want to get around Java restrictions in your Aspect, you can declare the Aspect “privileged“. Say you perform some logging from your Aspect, but the member you want to access … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[112,52],"tags":[129,131,130,132],"class_list":["post-533","post","type-post","status-publish","format-standard","hentry","category-android","category-java","tag-aop","tag-aspect","tag-aspectj","tag-privileged"],"_links":{"self":[{"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/posts\/533","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/comments?post=533"}],"version-history":[{"count":6,"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/posts\/533\/revisions"}],"predecessor-version":[{"id":539,"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/posts\/533\/revisions\/539"}],"wp:attachment":[{"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/media?parent=533"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/categories?post=533"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/blog.ansuz.nl\/index.php\/wp-json\/wp\/v2\/tags?post=533"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}