1.Environment类
简单介绍:http://www.cnblogs.com/mengdd/p/3742623.html
详细介绍:http://www.2cto.com/kf/201408/327215.html
2.File类
http://www.3lian.com/edu/2012/12-24/50689.html
file.getPath() getAbsolutePath() getCanonicalPath()区别:http://www.cnblogs.com/xulianbo/archive/2011/08/26/2154027.html
3.RandomAccessFile及实现存储的方法:http://blog.csdn.net/ztp800201/article/details/7322110