java - Setting webapprootkey no-web.xml -

i'm migrating web app spring 3.2 , enjoying web.xml-free configuration. 1 part that's remaining setting webapp root key, did in web.xml so:

<context-param> <param-name>webapprootkey</param-name> <param-value>webapproot</param-value> </context-param> 

i know spring creates default key, in case i'm running multiple versions of same war , need set key different value in each. optimally i'd take value properties file , use rootkey.

i imagine somewhere here:

public class webappinitializer implements webapplicationinitializer {     private static final logger logger = logger.getlogger(webappinitializer.class);  @override public void onstartup(servletcontext servletcontext) throws servletexception {     // create root appcontext        annotationconfigwebapplicationcontext rootcontext = new annotationconfigwebapplicationcontext();        rootcontext.register(appconfig.class);         servletcontext.addlistener(new webapprootlistener());      // manage lifecycle of root appcontext        servletcontext.addlistener(new contextloaderlistener(rootcontext));        //servletcontext.setinitparameter("defaulthtmlescape", "true");      // main spring mvc servlet.        servletregistration.dynamic springapp = servletcontext.addservlet(           "springapp", new dispatcherservlet(rootcontext));             springapp.setloadonstartup(1);        set<string> mappingconflicts = springapp.addmapping("/"); ...etc... 

thanks can offer advice!

the first part simple:

servletcontext.setinitparameter("webapprootkey", getrootkey()); 

and rootkey, in case added application.properties file maven build,

private string getrootkey() {     properties prop = new properties();     classloader loader = thread.currentthread().getcontextclassloader();                inputstream stream = loader.getresourceasstream("application.properties");     string key=null;     try {         prop.load(stream);         key = prop.getproperty("rootkey");     } catch  (exception e) {         throw new runtimeexception("cannot load webapprootkey", e);     }     return key; }