angular.jsp

<script>
// inject inlined constants
angular.module('app.constants', [])
	.constant('contextPath', '${pageContext.request.contextPath}');
</script>

example.js

// create the filter that uses the context path constant
angular.module('app.filters', ['app.constants'])
  .filter('relativeUrl', ['contextPath', function(contextPath) {
		return function(url) {
			return contextPath + url;
		};
	}]);

// inject the filter and use the context path
angular.module('app.services', ['ngResource']).
  factory('PlaceService', ['$filter', '$resource', function($filter, $resource) {
		var relativeUrl = $filter('relativeUrl');
		return $resource(relativeUrl('/rest/places/:id'), {id: '@id'});
	}]);