added toString() method


git-svn-id: https://svn.apache.org/repos/asf/directory/shared/trunk@1572457 13f79535-47bb-0310-9956-ffa450edef68
fixed javadoc


git-svn-id: https://svn.apache.org/repos/asf/directory/shared/trunk@1572458 13f79535-47bb-0310-9956-ffa450edef68