Context Parameters value not string

Question

Let's say you write a Deployment Descriptor with some context parameters and you want one of them to be an object,unfortunatelly I read that you cand only add string values to the tag.

Is there a way to do this?I understood an example when it came to a database because you can put the look-up name.

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   ....>
 <context-param>
   <param-name>foo</param-name>
   <param-value>new foo()</param-value>
 <servlet>
  <servlet-name>BeerParamTests</servlet-name>
  <servlet-class>TestInitParams</servlet-class>
  <init-param>
   <param-name>adminEmail</param-name>
   <param-value> likewecare@wikewdfs</param-value>
  </init-param>
 </servlet>
<servlet-mapping>
 <servlet-name>BeerParamTests</servlet-name>
 <url-pattern>/Tester.do</url-pattern>
</servlet-mapping>

@Arvind I am not developing on a specific framework as I am trying to learn a bit of Java EE — tudoricc, Jul 14 '14 at 12:16
@tudoricc, possibly you can go for reflection to build instance based on class qualified name given in the context-param — , Jul 14 '14 at 12:22

score 1 · Answer 1 · answered Jul 14 '14 at 12:28

<context-param>
   <param-name>foo</param-name>
   <param-value>new foo()</param-value>
</context-param>

This will just store new foo() as String.

param-name and param-value is based as key-value pair.

key to retrive the String stored as value no use of this kind of value as it will only return String

String foo=getServletContext().getInitParameter("foo");//result : new foo()

Let's say you write a Deployment Descriptor with some context parameters and you want one of them to be an object

No. You can't store Object to the Deployment descriptor.Only String parameters are allowed.

score 1 · Accepted Answer · answered Jul 14 '14 at 12:43

1

<context-param> <param-name>foo</param-name> <param-value>com.edu.Foo</param-value> </context-param>

In you java code, try the below

Class.forName(getServletContext().getInitParameter("foo")).newInstance();

but you will get only the empty object without any values assigned to the properties. will it work for you?

answered Jul 14 '14 at 12:43

whoami

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Yes it does,though I can not call a certain method from that class you can still do something with that class – tudoricc Jul 14 '14 at 12:54

Context Parameters value not string

2 Answers2