简单的session类，用于手机短信应用。主要包括setAttribute（），getAttribute(), removeSession()个方法，set方法在没有session时自动建立一个session.-Simple type of session for the application of a cell phone text message. Mainly include the setAttribute (), getAttribute (), removeSession () m

The "getAttribute(name)" method returns an empty string if no value was assigned to an attribute and no default value was given in the DTD file.

The "getAttribute(name)" method returns an attribute value by name.

图片转换方面内容，采用DOM编程艺术知识(about geElementbute,change picture)