The returnattribute should equate to the return type of the method.
retur n属性应该与方法的返回类型相同。
2
Both of these methods return an empty string if the attribute doesn't exist.
如果属性不存在,那么这两种方法都将返回空字符串。
3
For a given group membership attribute for a given LDAP, it is necessary to know how the given LDAP manages its membership attribute, and what values this attribute will return.