Environment entries, defined using <env-entry>, provide a way of specifying deployment time parameters to J2SE Web applications. Note that the servlet context initialization parameters could be defined using <context-param>, but <env-entry> is the preferred way because application deployers to configure such applications parameters by explicitly specifying the name, type and values for them.
The following sample describes the syntax of <env-entry> as specified in the J2SE standard deployment descriptors:
<env-entry> <description> Send pincode by mail </description> <env-entry-name> mailPincode </env-entry-name> <env-entry-value> false </env-entry-value> <env-entry-type> java.lang.Boolean </env-entry-type> </env-entry>
The <env-entry-type> tag specifies a fully qualified class name for the entry. Here is a code snippet to lookup the <env-entry> using JNDI from a servlet or JSP:
Context initContext = new InitialContext(); Boolean mailPincode = (Boolean) initContext.lookup("java:comp/env/mailPincode"); // one could use relative names into the sub-context Context envContext = initContext.lookup("java:comp/env"); Boolean mailPincode = (Boolean) envContext.lookup("mailPincode");