org.eclipse.digitaltwin.basyx.http.Base64UrlEncoder Maven / Gradle / Ivy
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* Copyright (C) 2023 the Eclipse BaSyx Authors
*
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*
* The above copyright notice and this permission notice shall be
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package org.eclipse.digitaltwin.basyx.http;
import java.net.URLDecoder;
import java.nio.charset.StandardCharsets;
import java.util.Base64;
/**
* Basic logic for Base64Url encoding and decoding
*
* @author gordt, schnicke, mateusmolina
*/
public class Base64UrlEncoder {
public static String encode(String plainValue) {
// There are multiple ways to handle the padding - we decided
// to cut off the padding, since multiple encodings may lead to confusion.
// https://www.rfc-editor.org/rfc/rfc4648#section-5
// https://www.rfc-editor.org/rfc/rfc4648#section-3.2
byte[] bytes = plainValue.getBytes(StandardCharsets.UTF_8);
String base64urlEncoded = Base64.getUrlEncoder().encodeToString(bytes);
return base64urlEncoded.replace("=", "");
}
public static String decode(String encodedValue) {
// Some will encode the padding...
if (encodedValue.contains("%3D")) {
encodedValue = URLDecoder.decode(encodedValue, StandardCharsets.US_ASCII);
}
// Some will cut the padding...
var incompleteFourChars = encodedValue.length() % 4;
if (incompleteFourChars > 0)
encodedValue += "==".substring(0, 4 - incompleteFourChars);
byte[] decode = Base64.getUrlDecoder().decode(encodedValue.getBytes(StandardCharsets.US_ASCII));
return new String(decode, StandardCharsets.UTF_8);
}
}