Convert UUID To BASE64 and vice-versa

                                
                                    import org.apache.commons.codec.binary.Base64;

import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

public class RunJavaProgram {
    public static void getValue() {
        try {
            // select token from authtoken where user_id = ;
            List strList = new ArrayList<>();
            strList.add("a4a6c4ed-86b2-452e-bb0c-d7593e1fd0f6");
            strList.add("a8a0f8b4-ae16-4607-86d5-055d87f83d24"); // 635
            strList.add("1e5f9348-b979-4fa9-9998-b67b61128874"); // 636
            strList.forEach(s -> System.out.println(s + "::Decrypted Token - " + uuidToBase64(s)));
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
    }

    /**
     * Convert UUID to Base64
     * http://stackoverflow.com/questions/772802/storing-uuid-as-base64-string
     *
     * @param str
     * @return
     */
    public static String uuidToBase64(String str) {
        Base64 base64 = new Base64();
        UUID uuid = UUID.fromString(str);
        ByteBuffer bb = ByteBuffer.wrap(new byte[16]);
        bb.putLong(uuid.getMostSignificantBits());
        bb.putLong(uuid.getLeastSignificantBits());
        return base64.encodeBase64URLSafeString(bb.array());
    }

    /**
     * Convert Base64 to UUID
     *
     * @param str
     * @return
     */
    public static String uuidFromBase64(String str) {
        Base64 base64 = new Base64();
        try {
            byte[] bytes = base64.decodeBase64(str);
            ByteBuffer bb = ByteBuffer.wrap(bytes);
            UUID uuid = new UUID(bb.getLong(), bb.getLong());
            return uuid.toString();
        } catch (Exception e) {
            return "";
        }
    }
}