{"id":2300,"date":"2017-02-27T11:15:43","date_gmt":"2017-02-27T09:15:43","guid":{"rendered":"http:\/\/hasselba.ch\/blog\/?p=2300"},"modified":"2017-02-27T18:55:26","modified_gmt":"2017-02-27T16:55:26","slug":"domino-rest-listeners-for-initialization-destroying-of-a-servlet","status":"publish","type":"post","link":"https:\/\/hasselba.ch\/blog\/?p=2300","title":{"rendered":"Domino & REST: Listeners for Initialization & Destroying of a Servlet"},"content":{"rendered":"

If you need to know when your Servlet is initialized or destroyed, you can use a ServletContextListener<\/em> in your application.<\/p>\n

First, create the class AppServletContextListener<\/em> and implement the javax.servlet.ServletContextListener <\/em>interface.<\/em> This provides two methods for capturing the events: contextInitialized<\/em> and contextDestroyed:<\/em><\/p>\n

package ch.hasselba.servlet;\r\n\r\nimport javax.servlet.ServletContextEvent;\r\nimport javax.servlet.ServletContextListener;\r\n\r\npublic class AppServletContextListener\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 implements ServletContextListener{\r\n\r\n\u00a0\u00a0 \u00a0@Override\r\n\u00a0\u00a0 \u00a0public void contextDestroyed(ServletContextEvent event) {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0System.out.println(\"ServletContextListener destroyed\");\r\n\u00a0\u00a0 \u00a0}\r\n\r\n\u00a0\u00a0 \u00a0@Override\r\n\u00a0\u00a0 \u00a0public void contextInitialized(ServletContextEvent event) {\r\n\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0System.out.println(\"ServletContextListener started\");\r\n\u00a0\u00a0 \u00a0}\r\n}<\/code><\/pre>\n
The ServletContextEvent<\/em><\/a> allows you to access the ServletContext<\/em><\/a> if required.<\/p>\n
Now you have to register the listener in your web.xml<\/em>:<\/p>\n
<web-app>\r\n\u00a0\u00a0\u00a0\u00a0 <listener>\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <listener-class>\r\n\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0\u00a0 ch.hasselba.servlet.AppServletContextListener\r\n\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/listener-class>\r\n\u00a0\u00a0\u00a0 <\/listener>\r\n<\/web-app><\/code><\/pre>\n
As soon as you start or stop the HTTP task, the Listener is called, and you can execute some application specific code (i.e. shutdown threads, bring out the garbage, etc.)<\/p>\n
\"\"<\/a>\"\"<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
If you need to know when your Servlet is initialized or destroyed, you can use a ServletContextListener in your application. First, create the class AppServletContextListener and implement the javax.servlet.ServletContextListener interface. This provides two methods for capturing the events: contextInitialized and … Weiterlesen →<\/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":[89,116,61,82],"tags":[118,7,117,60,119,12],"class_list":["post-2300","post","type-post","status-publish","format-standard","hentry","category-java","category-jee","category-rest","category-server","tag-apache-wink","tag-domino","tag-jee","tag-rest","tag-servlet","tag-web"],"_links":{"self":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2300","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=2300"}],"version-history":[{"count":4,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2300\/revisions"}],"predecessor-version":[{"id":2306,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2300\/revisions\/2306"}],"wp:attachment":[{"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2300"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2300"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hasselba.ch\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2300"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}