Hash a password with SHA1 in java

Question

I want to insert a password to my database using SHA1 hash I do it manually in phpmyadmin by choosing the function sha1 but how to do this using Java ??

Any Idea ? Thank you!

Answer 1

If you must use java :

import java.io.ByteArrayInputStream;
import java.security.MessageDigest;

public class SHACheckSumExample 
{
    public static void main(String[] args)throws Exception
    {
        MessageDigest md = MessageDigest.getInstance("SHA-1");
        ByteArrayInputStream fis = new ByteArrayInputStream(args[1].getBytes());

        byte[] dataBytes = new byte[1024];

        int nread = 0; 
        while ((nread = fis.read(dataBytes)) != -1) {
          md.update(dataBytes, 0, nread);
        };
        byte[] mdbytes = md.digest();

        //convert the byte to hex format method 1
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < mdbytes.length; i++) {
          sb.append(Integer.toString((mdbytes[i] & 0xff) + 0x100, 16).substring(1));
        }

        System.out.println("Hex format : " + sb.toString());

       //convert the byte to hex format method 2
        StringBuffer hexString = new StringBuffer();
        for (int i=0;i<mdbytes.length;i++) {
          hexString.append(Integer.toHexString(0xFF & mdbytes[i]));
        }

        System.out.println("Hex format : " + hexString.toString());
    }
}

I would, for performance reasons, suggest seeing if your database has SHA support. I know Postgres does , not sure about other systems.