java 加密技术总结

Important Notes

1. In order to keep the size of the signed jar files down the regression tests are no longer included in them. See the bctest*.jar file for the appropriate JDK.[译文：为了减少jar文件大小，test 部分将不会包含在jar文件中，如果想进一步的了解，请看bctest*.jar文件！【译文仅供个人理解参考】]

2. The JCE classes are only distributed with the JDK 1.1, JDK 1.2, and JDK 1.3 JCE releases. The JDK 1.4-1.6 release just contains the provider and lightweight API. The JDK 1.0, J2ME, and the JDK 1.1 and later lightweight releases only include the Bouncy Castle lightweight cryptography API.

3. If you are using JDK 1.4, or later, you must use the signed jar for the provider and you must download the unrestricted policy files for the Sun JCE if you want the provider to work properly. The policy files can be found at the same place as the JDK download. Further information on this can be found in the Sun documentation on the JCE. If you have not installed the policy files you will see something like：

4. java.lang.SecurityException: Unsupported keysize or algorithm parameters
   		at javax.crypto.Cipher.init(DashoA6275)
   
   		【如果没有安装java密码策略文件的话，就会抛出这个例外...】

5.