java - Velocity + Spring -

i attempting setup webapp above components. i've jumped last hurdle integrating spring & velocity tools. saw this post morning, , updated different answer provided. however, once attempted add in parametertool 1 of templates so:

#foreach( $key in $params.keyset() )     $key = $params.getvalue($key) <br /> #end 

i receive npe java.lang.unsupportedoperationexception: request null. parametertool must initialized first! according i've read means tooling configured properly, doesn't have access request. note: receive error accepted solution well.

has been able use these tools spring? seems it's known deficiency there open jira open jira spr-5514

a modified version of the accepted answer this question resolves issue.

instead of returning viewcontext need return viewtoolcontext. need prepare toolboxes , set them on session / request applicable:

you need initialize toolcontext in whichever manner need (look @ provided answer here on how updated apis, you're going need access toolboxfactory.

the modified createvelocitycontext method need prepare toolboxes prior creating viewtoolcontext in following manner:

protected context createvelocitycontext(map <string, object> model,                                          httpservletrequest request,                                         httpservletrespsone response)                                          throws exception {      initvelocitycontext();  //still keep toolcontext static                             //will need add                              //the servletcontext -- left exercise     preparetoolboxes(request, response);     context context =          new viewtoolcontext(getvelocityengine(), request,                                  response, getservletcontext());     //set model attrs context     ....     return context; }  private void preparetoolboxes(final httpservletrequest request,                                final httpservletresponse response) {     string key = toolbox.class.getname();     if (factory.hastools(scope.request && request.getattribute(key) == null) {         toolbox requesttools = factory.createtoolbox(scope.request);         request.setattribute(key, requesttools);     }     if (factory.hastools(scope.session) {        httpsession session = request.getsession();        synchronized(factory) {            //follow pattern above        }     } }