{"id":963,"date":"2012-10-10T11:22:21","date_gmt":"2012-10-10T09:22:21","guid":{"rendered":"http:\/\/hasselba.ch\/blog\/?p=963"},"modified":"2012-10-11T11:25:14","modified_gmt":"2012-10-11T09:25:14","slug":"quick-n-dirty-a-simple-isrecycled-method","status":"publish","type":"post","link":"https:\/\/hasselba.ch\/blog\/?p=963","title":{"rendered":"Quick-n-Dirty: A simple isRecycled() method"},"content":{"rendered":"<p><strong>Update: Please read the <a title=\"Quick-n-Dirty: A simple isRecycled() method (2)\" href=\"https:\/\/hasselba.ch\/blog\/?p=970\">second article<\/a> &#8211; there you will find a better version.<br \/>\n<\/strong><\/p>\n<p>You will find that the domino java API does not have a suitable method to test if a domino object was already recycled or not. And because of the internal caching of some method calls it is not reliable to check for example for a specific property with a try\/catch block.<\/p>\n<p>But domino objects have a private property <em>isdeleted<\/em> which is transient and gives us the required information. With <a title=\"oracle.com: The Reflection API\" href=\"http:\/\/docs.oracle.com\/javase\/tutorial\/reflect\/index.html\" target=\"_blank\">Java Reflection<\/a> it is possible to access this property:<\/p>\n<pre>package ch.hasselba.domino;\r\n\r\nimport java.lang.reflect.Field;\r\n\r\nimport lotus.domino.Base;\r\nimport lotus.domino.local.NotesBase;\r\n\r\n\/**\r\n\u00a0* DominoUtil a library containing usefull Tools \/ Methods for domino\r\n\u00a0* \r\n\u00a0* @author Sven Hasselbach\r\n\u00a0* @category Domino\r\n\u00a0* @category Tools\r\n\u00a0* @version 1.2\r\n\u00a0*\/\r\npublic class DominoUtil {\r\n\r\n\u00a0\u00a0 \u00a0private static Field isDeleted;\u00a0\u00a0 \u00a0\r\n\r\n\u00a0\u00a0 \u00a0\/**\r\n\u00a0\u00a0 \u00a0 * checks if a domino object is already recycled\r\n\u00a0\u00a0 \u00a0 * \r\n\u00a0\u00a0 \u00a0 * @param lotus.domino.local.NotesBase\r\n\u00a0\u00a0 \u00a0 *\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 obj to check\r\n\u00a0\u00a0 \u00a0 * @author Sven Hasselbach\r\n\u00a0\u00a0 \u00a0 * @category Domino\r\n\u00a0\u00a0 \u00a0 * @category Tools\r\n\u00a0\u00a0 \u00a0 * @version 1.1\r\n\u00a0\u00a0 \u00a0 *\/\r\n\u00a0\u00a0 \u00a0public static boolean isRecycled(NotesBase obj) {\r\n\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0if( isDeleted == null )\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0initIsDeleted();\r\n\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0try {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0return isDeleted.getBoolean(obj);\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0} catch (Exception e) {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0e.printStackTrace();\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0}\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0return false;\r\n\u00a0\u00a0 \u00a0}\r\n\r\n\u00a0\u00a0 \u00a0\/**\r\n\u00a0\u00a0 \u00a0 * checks if a domino object is already recycled\r\n\u00a0\u00a0 \u00a0 * \r\n\u00a0\u00a0 \u00a0 * @param lotus.domino.Base\r\n\u00a0\u00a0 \u00a0 *\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 obj to check\r\n\u00a0\u00a0 \u00a0 * @author Sven Hasselbach\r\n\u00a0\u00a0 \u00a0 * @category Domino\r\n\u00a0\u00a0 \u00a0 * @category Tools\r\n\u00a0\u00a0 \u00a0 * @version 1.1\r\n\u00a0\u00a0 \u00a0 *\/\r\n\u00a0\u00a0 \u00a0public static boolean isRecycled(Base obj) {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0return isRecycled( (NotesBase) obj );\r\n\u00a0\u00a0 \u00a0}\r\n\r\n\u00a0\u00a0 \u00a0\/**\r\n\u00a0\u00a0 \u00a0 * inits Reflection of isDeleted field\r\n\u00a0\u00a0 \u00a0 *\/\r\n\u00a0\u00a0 \u00a0private static void initIsDeleted(){\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0try {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0isDeleted = lotus.domino.local.NotesBase.class\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0.getDeclaredField(\"isdeleted\");\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0isDeleted.setAccessible(true);\r\n\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0} catch (Exception e) {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0e.printStackTrace();\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0}\r\n\u00a0\u00a0 \u00a0}\r\n\r\n}<\/pre>\n<p>Here is a short demonstration of the usage in an agent (it works in XPages \/ SSJS too):<\/p>\n<pre>import lotus.domino.*;\r\nimport ch.hasselba.domino.DominoUtil;\r\n\r\npublic class JavaAgent extends AgentBase {\r\n\r\n\u00a0\u00a0\u00a0 public void NotesMain() {\r\n\r\n\u00a0\u00a0\u00a0\u00a0\u00a0 try {\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Session session = getSession();\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 AgentContext agentContext = session.getAgentContext();\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Database db = session.getCurrentDatabase();\r\n\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 View v1 =\u00a0 db.getView( \"AllDocuments\" );\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 View v2 =\u00a0 db.getView( \"AllDocuments\" );\r\n\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println( \"Recycled: \" + \r\n             DominoUtil.isRecycled( v1 ) );\r\n\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 v2.recycle();\r\n\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 System.out.println( \"Recycled: \" + \r\n            DominoUtil.isRecycled( v1 ) );\r\n\r\n\u00a0\u00a0\u00a0\u00a0\u00a0 } catch(Exception e) {\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 e.printStackTrace();\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 }\r\n\u00a0\u00a0 }\r\n}<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Update: Please read the second article &#8211; there you will find a better version. You will find that the domino java API does not have a suitable method to test if a domino object was already recycled or not. And &hellip; <a href=\"https:\/\/hasselba.ch\/blog\/?p=963\">Weiterlesen <span class=\"meta-nav\">&rarr;<\/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":[89,76],"tags":[7,31,5,32],"class_list":["post-963","post","type-post","status-publish","format-standard","hentry","category-java","category-ssjs","tag-domino","tag-java","tag-ssjs","tag-tipp"],"_links":{"self":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/963","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=963"}],"version-history":[{"count":7,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/963\/revisions"}],"predecessor-version":[{"id":967,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/963\/revisions\/967"}],"wp:attachment":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=963"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=963"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=963"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}