import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.EOFException;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Base64;

import java.util.List;

import der.tools.DEREncoder;

/**

* Class that produces a DER encoded byte array based on a passed in encoding.

*/

public class DEREncoderDemo

{

private static byte[] baseCert = Base64.getDecoder().decode(

"MIIDbDCCAtWgAwIBAgIBADANBgkqhkiG9w0BAQQFADCBtzELMAkGA1UEBhMCQVUx"

+ "ETAPBgNVBAgTCFZpY3RvcmlhMRgwFgYDVQQHEw9Tb3V0aCBNZWxib3VybmUxGjAY"

+ "BgNVBAoTEUNvbm5lY3QgNCBQdHkgTHRkMR4wHAYDVQQLExVDZXJ0aWZpY2F0ZSBB"

+ "dXRob3JpdHkxFTATBgNVBAMTDENvbm5lY3QgNCBDQTEoMCYGCSqGSIb3DQEJARYZ"

+ "d2VibWFzdGVyQGNvbm5lY3Q0LmNvbS5hdTAeFw0wMDA2MDIwNzU1MzNaFw0wMTA2"

+ "MDIwNzU1MzNaMIG3MQswCQYDVQQGEwJBVTERMA8GA1UECBMIVmljdG9yaWExGDAW"

+ "BgNVBAcTD1NvdXRoIE1lbGJvdXJuZTEaMBgGA1UEChMRQ29ubmVjdCA0IFB0eSBM"

+ "dGQxHjAcBgNVBAsTFUNlcnRpZmljYXRlIEF1dGhvcml0eTEVMBMGA1UEAxMMQ29u"

+ "bmVjdCA0IENBMSgwJgYJKoZIhvcNAQkBFhl3ZWJtYXN0ZXJAY29ubmVjdDQuY29t"

+ "LmF1MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDgs5ptNG6Qv1ZpCDuUNGmv"

+ "rhjqMDPd3ri8JzZNRiiFlBA4e6/ReaO1U8ASewDeQMH6i9R6degFdQRLngbuJP0s"

+ "xcEE+SksEWNvygfzLwV9J/q+TQDyJYK52utb++lS0b48A1KPLwEsyL6kOAgelbur"

+ "ukwxowprKUIV7Knf1ajetQIDAQABo4GFMIGCMCQGA1UdEQQdMBuBGXdlYm1hc3Rl"

+ "ckBjb25uZWN0NC5jb20uYXUwDwYDVR0TBAgwBgEB/wIBADA2BglghkgBhvhCAQ0E"

+ "KRYnbW9kX3NzbCBnZW5lcmF0ZWQgY3VzdG9tIENBIGNlcnRpZmljYXRlMBEGCWCG"

+ "SAGG+EIBAQQEAwICBDANBgkqhkiG9w0BAQQFAAOBgQCsGvfdghH8pPhlwm1r3pQk"

+ "msnLAVIBb01EhbXm2861iXZfWqGQjrGAaA0ZpXNk9oo110yxoqEoSJSzniZa7Xtz"

+ "soTwNUpE0SLHvWf/SlKdFWlzXA+vOZbzEv4UmjeelekTm7lc01EEa5QRVzOxHFtQ"

+ "DhkaJ8VqOMajkQFma2r9iA==");

private static byte[] cert_multiv_dn_ber = Base64.getDecoder().decode(

"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");

private static byte[] cert_multiv_dn_der = Base64.getDecoder().decode(

"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");

public static void main(String[] args)

throws Exception

{

DEREncoder derEnc = new DEREncoder(DEREncoder.LENGTHS | DEREncoder.SORT_SETS);

byte[] derOut = derEnc.toDER(baseCert);

System.out.println(Arrays.equals(derOut, baseCert));

derOut = derEnc.toDER(cert_multiv_dn_der);

System.out.println(Arrays.equals(derOut, cert_multiv_dn_der));

derOut = derEnc.toDER(cert_multiv_dn_ber);

System.out.println(Arrays.equals(derOut, cert_multiv_dn_der));

derOut = derEnc.toDER(cert_multiv_dn_ber);

System.out.println(Arrays.equals(derOut, cert_multiv_dn_der));

System.out.println(Arrays.equals(cert_multiv_dn_ber, cert_multiv_dn_der));

}

}