File list (Check if you may need any files):
习09.15 对文本文件进行加密和解密操作\.classpath
.....................................\.project
.....................................\Dest.txt
.....................................\old.txt
.....................................\source - 复制.txt
.....................................\source.txt
.....................................\.rc\Encryptable.java
.....................................\...\EncryptText.java
.....................................\bin\Encryptable.class
.....................................\...\EncryptText.class
.....................................\...\Plus.class
.....................................\src
.....................................\bin
习09.15 对文本文件进行加密和解密操作