There is an value-param example:

  <component>

    <key>org.exoplatform.portal.config.UserACL</key>

    <type>org.exoplatform.portal.config.UserACL</type>   

    <init-params>        

...

      <value-param>

        <name>access.control.workspace</name>

        <description>groups with memberships that have the right to access the User Control Workspace</description>

        <value>*:/platform/administrators,*:/organization/management/executive-board</value> 

      </value-param> 

...

  </component>

The UserACL class accesses to the value-param in its constructor.

package org.exoplatform.portal.config;

public class UserACL {


  public UserACL(InitParams params) {

    UserACLMetaData md = new UserACLMetaData();

    ValueParam accessControlWorkspaceParam = params.getValueParam("access.control.workspace");

    if(accessControlWorkspaceParam != null) md.setAccessControlWorkspace(accessControlWorkspaceParam.getValue());

...