KeyGenerator 支持有以下几种
		
		
		
				- 
						DES: 56 bits 
 
				- 
						Triple DES: 112 bits 
 
				- 
						Blowfish: 56 bits 
 
				- 
						HmacMD5: 64 bytes 
 
				- 
						HmacSHA1: 64 bytes 
 
		
		
		
		
				KeyPairGenerator
				
支持的密钥算法只有DH,RSA的需要到BC找
		
		
		
				- 
						Diffie-Hellman: 1024 bits 
 
		
		
		
		
				AlgorithmParameterGenerator
				
也是只支持Diffie-Hellman,不支持RSA
		
		
		
				- 
						Diffie-Hellman: 1024 bits