Question

I cannot figure out how to implement this on my application.

I want to have an xml (or some file) where the person in charge of the administration of the app chooses where the Root_Dir is.

Right now it is hard-coded something like C:\MyAppRootDir but I want that this path could be modified whenever the admin wants.

Any ideas?

Cheers

Answer 1

There are several ways to provide external configuration to a webapp.

1. Create a properties file and put it in one of the paths covered by webapp’s runtime classpath, or add its path to the webapp’s runtime classpath.

   E.g. /path/to/config.properties with this content

   xmlrootdir=C:\MyAppRootDir
   

   You’ll be able to grab it by the classloader.

   Properties properties = new Properties();
   properties.load(Thread.currentThread().getContextClassLoader().getResourceAsStream("config.properties"));
   String xmlrootdir = properties.getProperty("xmlrootdir");
   // ...
   

   Based on your question history, you’re using/targeting Tomcat. The admin could edit the shared.loader entry of its /conf/catalina.properties to point to the folder where this properties file is located.

   shared.loader=/path/to
   

2. Add a VM argument to Tomcat startup script.

   -Dconfig.xmlrootdir=C:\MyAppRootDir
   

   It’s available as follows:

   String xmlrootdir = System.getProperty("config.xmlrootdir");
   // ...
   

3. Set an environment variable.

   SET CONFIG_XMLROOTDIR=C:\MyAppRootDir
   

   It’s available as follows:

   String xmlrootdir = System.getenv("CONFIG_XMLROOTDIR");
   // ...