A DESCRIPTION OF THE REQUEST :
When calling the method:
java.security.MessageDigest#getInstance(java.lang.String algorithm)
then java.security.NoSuchAlgorithmException if no Provider supports a MessageDigestSpi implementation for the specified.


JUSTIFICATION :
Following Java Tutorial, Lesson: Exceptions, section: Unchecked Exceptions — The Controversy:

"One case where it is common practice to throw a RuntimeException is when the user calls a method incorrectly. For example, a method can check if one of its arguments is incorrectly null. If an argument is null, the method might throw a NullPointerException, which is an unchecked exception."

I think when a developer try to get an algorithm that is not supported by the platform, that is developer mistake, not environment condition. He/she have to know which algorithm is supported before he/she decide to use it. So java.security.NoSuchAlgorithmException should be a runtime exception or MessageDigest#getInstance should throw runtime exception.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
In most time, I just call MessageDigest.getInstance("MD5") on Sun JDK/Windows XP. I would not to catch NoSuchAlgorithmException because I'm sure that it never occurs. In some case I try to get an algorithm that is not supported by the platform, I would like to see a runtime exception so I can fix my bug.