core/src/main/java/org/springframework/security/access/vote/RoleHierarchyVoter.java
@Override
	Collection<? extends GrantedAuthority> extractAuthorities(
			Authentication authentication) {
		return roleHierarchy.getReachableGrantedAuthorities(authentication
				.getAuthorities());
	}
@Override
	Collection<? extends GrantedAuthority> extractAuthorities(
			Authentication authentication) {
		return roleHierarchy.getReachableGrantedAuthorities(authentication
				.getAuthorities());
	}
Calls the <tt>RoleHierarchy</tt> to obtain the complete set of user authorities.