why '/test' goes to 'localhost:8080/test' instead of 'localhost:8080/rootcontext/test'

I have created a dynamic web project in eclipse using maven 3 .i used from angularjs in client side and spring and spring security as backend technology.

when i run project it correctly redirects to to the root context and login page,

but when i want to run this javascript :

angular.module('common')
.controller('BaseFormCtrl', ['$scope', '$http', function ($scope, $http) {

           $scope.login = function (username, password) {

        $http({
            method: 'POST',
            url: '/authenticate',
            data: postData,
            headers: {
                "Content-Type": "application/x-www-form-urlencoded",
                "X-Login-Ajax-call": 'true'
            }
        })
        .then(function(response) {
            if (response.data == 'ok') {
                window.alert("login success");
            }
            else {
                window.alert("login faild");
            }
        });
    }


}])

it return this error:

POST http://localhost:8080/authenticate 404 (Not Found)

but i expect that it call this: http://localhost:8080/avl-web/authenticate

which avl-web is my root context

thanks in advanced