Handling digest output

Question

Please consider the following code. It seems to work fine. However, the output clearly includes unusual characters such as squares and characters from printed languages other than English (I recognized some as being used in German - many others I have never seen before).
Am I correct in assuming that the output from function digest is just binary data that is not often printable using only alpha-numeric characters? If not, how would I modify the code I am showing in order to have the complete digest shown on the form as a string consisting only of alpha-numeric characters?
I want to store the result in one database, containing user ID information, and in a second as a user ID for records containing potentially sensitive data. Is the result of function digest always unique given unique input data, or will I need extra code to make the values I store in the database unique? The objective for using the output from a digest is to make it more difficult to relate the data in one database to a specific person. I want only my own programs to easily make such a connection (and all of this code resides on the server, within servlets).
The databases I am using include PostgreSQL and MySQL. When the application is deployed, they will be configured to accept connections only from specific non-routable IP addresses. But, I am assuming that even if I do al the usual things to harden my site, I still ought to do things like this within an application so that if my administrative security measures fail, that failure does not automatically mean the data is easily accessable/usable.
What can I do to ensure that the result of my digest does not create problems for the RDBMS I am using, and that I can use it as intended?
    private void ProceedMouseClicked(java.awt.event.MouseEvent evt) {
        MessageDigest md=null;
        try {
            md = MessageDigest.getInstance("SHA");
        } catch (java.security.NoSuchAlgorithmException nsae) {
            OutputText.setText("OOPS");
        if (md == null) {
            OutputText.setText("OOPS2");
            return;
        byte[] data = InputText.getText().getBytes();
        md.update(data);
        byte[] result = md.digest();
        String rv = new String(result);
        OutputText.setText(rv);
    }Thanks,
Ted

Answer 1

hi,
this is to inform you that,
there is an issue with SPACE in function module:
WFMC_MESSAGES_PROCESS
process original output
        if pi_be_quiet eq space.
          MESSAGE S108.
        endif.
      WHEN C_PROCESS_REPEAT.
please sit with your ABAPER and try to debugg it on it.
update the forum
regards,
balajia