Java Servlets - Storing a list of values in web.xml (multiple param-value's for single param-name)

Servlet spec says that you can have only one value for any context parameter. So, you are left with going with delimited list only.

<context-param>
  <param-name>validHosts</param-name>
  <param-value>example1.com,example2.com,.....</param-value>
</context-param>

Put each param on its own line. I did the following recently and it works fine:

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>
        /WEB-INF/spring-beans.xml
        /WEB-INF/security-config.xml    
    </param-value>
</context-param>

Yes, just use delimiters (as no other options available for this):

<context-param>
    <param-name>validHosts</param-name>
    <param-value>example1.com,example2.com,example3.com</param-value>
</context-param>



then simply
String[] validHosts = param.split(","); // not really much to do