基于DES的对称加密、利用java中的相关类实现对指定字符串的加解密、实现图形界面-DES based on symmetric encryption, the use of java in the relevant class implements the specified string encryption and decryption, implement graphical interface

包含各种实用的java工具类，例如对文件流、字符串加密解密、打印、字符串编码、邮件等工具-Contains a variety of useful java tools, such as file flow, string encryption and decryption, printing, string coding, mail and other tools