说明：  SNMP++是HP公司开发的支持SNMP的第三方软件，该软件有70多个类。该文档讲述了里面的最重要的类的属性和方法，对学习者很有帮助
(HP SNMP++ was developed to support third-party SNMP software, which more than 70 classes. This document describes the most important classes inside the properties and methods useful for learners)