基于JDBC的数据库封装类，实现了JDBC更高一层的函数封装，方法如 public List getResultList(String sql),实现了连接和异常的自动处理。-JDBC-based database package category, achieved a higher level of function JDBC package, methods such as public List getResultList (String sql), the realization of the connection and the automatic processing of anomalies.