JAVA写的可以用RSA加密解密的代码，随机产生密钥，数据格式是长整型，代码包含求逆元、大数取模模块。-Can be written in JAVA RSA encryption and decryption code, randomly generated key, the data format is a long integer, the code contains the inverse element, large numbers modulo module.

Java 实现DES文件加密、MD5获取数字签名和文件验证、RSA签名加密。分为接收端和发送端。-Java implementation of the DES file encryption, MD5 obtaining digital signatures and document verification, RSA signature encryption. Into the receiver and transmitter.