import java.io.UnsupportedEncodingException;
import java.util.Base64;

public class Base64Test {
    public static void main(String[] args) throws UnsupportedEncodingException {
        final String value = "test";

        final byte[] encodedValue = Base64.getEncoder().encode(value.getBytes("UTF-8"));

        final byte[] decodedValue = Base64.getDecoder().decode(encodedValue);

        // should print 'test'!
        System.out.println(new String(decodedValue, "UTF-8"));
    }
}