Android Question How sign string with certificate in B4A like this java example?

[Sasa]

package example;
import java.io.FileInputStream;
import java.security.Key;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.Signature;
import org.apache.commons.codec.digest.DigestUtils;


public class ResultFinal {
public static void main( String[] args ) {

String Text1 = "123456789";

String rezultat = Text1;

String datVrij = new SimpleDateFormat( "dd.MM.yyyy HH:mm:ss" ).format( new
Date() );

rezultat = rezultat + datVrij;

// RSA-SHA1 sign
byte[] signed = null;
try {
FileInputStream file_inputstream = new
FileInputStream("D:\\Certificate\\key.jks");
KeyStore keyStore = KeyStore.getInstance( "JKS" );
keyStore.load( file_inputstream, "password".toCharArray() );
Key privatni = keyStore.getKey( "alias", " password ".toCharArray() );
Signature biljeznik = Signature.getInstance( "SHA1withRSA" );
biljeznik.initSign( ( PrivateKey )privatni );
biljeznik.update( rezultat.getBytes() );
signed = biljeznik.sign();
}
catch ( Exception e ) {

e.printStackTrace();
}
// MD5
String rezultatIspis = DigestUtils.md5Hex( signed );

System.out.println( "CODE IS: " + rezultatIspis
);
}
}

 

[Erel]

You can use the Encryption library to sign data. Don't use the keystore to store the key. It will only make things more complicated.