core/src/main/java/org/springframework/security/core/authority/mapping/MapBasedAttributes2GrantedAuthoritiesMapper.java
private Collection<GrantedAuthority> getGrantedAuthorityCollection(Object value) {
		Collection<GrantedAuthority> result = new ArrayList<>();
		addGrantedAuthorityCollection(result, value);
		return result;
	}
private Collection<GrantedAuthority> getGrantedAuthorityCollection(Object value) {
		Collection<GrantedAuthority> result = new ArrayList<>();
		addGrantedAuthorityCollection(result, value);
		return result;
	}
Convert the given value to a collection of Granted Authorities

@param value The value to convert to a GrantedAuthority Collection
@return Collection containing the GrantedAuthority Collection