byte[] unencodedPassword = password.getBytes();
MessageDigest md = null;

try {
// first create an instance, given the provider
md = MessageDigest.getInstance(algorithm);
} catch (Exception e) {
print ("Exception: " + e);

return password;
}

md.reset();

// call the update method one or more times
// (useful when you don't know the size of your data, eg. stream)
md.update(unencodedPassword);

// now calculate the hash
byte[] encodedPassword = md.digest();

StringBuffer buf = new StringBuffer();

for (int i = 0; i < encodedPassword.length; i++) {
if ((encodedPassword[i] & 0xff) < 0x10) {
buf.append("0");
}

buf.append(Long.toString(encodedPassword[i] & 0xff, 16));
}

return buf.toString();
}

/*
* Main bit of groovy starts here
*/
def DB='jdbc:postgresql://localhost/callbriefdb?useUnicode=true&characterEncoding=utf-8'
def USER='chutney'
def PASSWORD='pants'
def DRIVER='org.postgresql.Driver'

def sql = Sql.newInstance(DB,USER,PASSWORD,DRIVER)

//not really sure how to process a result set so just hacked it
sql.eachRow('select * from app_user where id <> 0′) { n -> newPw =encodePassword(n.pinNumber,”SHA”) ; sql.execute(”update app_user set password = ${newPw} where id = ${n.id}” )}