How to secure a REST Web Service using Spring Security - spring

Question

I am trying to secure my REST web services at the url /dispatcher/rest/**
My current design works fine if accessing the web service through browser - when I try to go to the REST url it redirects me to a login page to enter credentials, then redirects me to the web service data once logged in.
The problem is that when I try to access the web service through java code using RestTemplate, my code breaks. This occurs even if the user has already logged in and authenticated.
My spring-security.xml config file:
<beans:beans xmlns="http://www.springframework.org/schema/security"
xmlns:beans="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/security
http://www.springframework.org/schema/security/spring-security-3.2.xsd">
<!-- enable use-expressions -->
<http auto-config="true" use-expressions="true">
<intercept-url pattern="/dispatcher/admin**" access="hasRole('ROLE_ADMIN')" />
<intercept-url pattern="/dispatcher/rest/**" access="hasRole('ROLE_ADMIN')"/>
<!-- access denied page -->
<access-denied-handler error-page="/dispatcher/403" />
<form-login
login-page="/dispatcher/login"
default-target-url="/dispatcher/admin"
login-processing-url="/dispatcher/login_process"
authentication-failure-url="/dispatcher/login?error"
username-parameter="username"
password-parameter="password" />
<logout logout-success-url="/dispatcher/login?logout" logout-url = "/dispatcher/logout"/>
<!-- enable csrf protection -->
<csrf />
</http>
<authentication-manager>
<authentication-provider user-service-ref="myUserDetailsService" >
</authentication-provider>
</authentication-manager>
<beans:bean id="myUserDetailsService" class="com.shopping.services.MyUserDetailsService" />
</beans:beans>
Any help would be greatly appreciated!

Answer 1

The solution I found to access the web service is the following:
String username = ((UserDetails) principal).getUsername();
String password = ((UserDetails) principal).getPassword();
HttpClient client = new HttpClient();
client.getParams().setAuthenticationPreemptive(true);
Credentials defaultcreds = new UsernamePasswordCredentials(username, password);
restTemplate.setRequestFactory(new CommonsClientHttpRequestFactory(client));
client.getState().setCredentials(AuthScope.ANY, defaultcreds);
User x = restTemplate.getForObject("http://localhost:8080/Online_Shopping/dispatcher/rest/hello",User.class);