OAuth 2.1 PKCE

maxkey-common/src/main/java/org/maxkey/crypto/DigestUtils.java

@@ -61,6 +61,25 @@ public final class DigestUtils {
 		}
 		return cipherBASE64;
 	}
+	
+	/**
+     * @param simple
+     * @param algorithm MD5,SHA,SHA-1|SHA-256|SHA-384|SHA-512 then encodeBase64
+     * @return cipher
+     */
+    public static String digestBase64Url(String simple,String algorithm) {
+        MessageDigest messageDigest;
+        String cipherBASE64="";
+        try {
+            messageDigest = MessageDigest.getInstance(algorithm.toUpperCase());
+            messageDigest.update(simple.getBytes());
+            byte[] bCipher=messageDigest.digest();
+            cipherBASE64=Base64Utils.base64UrlEncode(bCipher);
+        } catch (NoSuchAlgorithmException e) {
+            e.printStackTrace();
+        }
+        return cipherBASE64;
+    }
 
 	//B64
 	public static String md5B64(String simple) {

maxkey-common/src/test/java/org/maxkey/crypto/Base64UtilsTest.java

@@ -42,7 +42,9 @@ public class Base64UtilsTest {
 		 System.out.println(Base64Utils.decode("AAMkADU2OWY1MGQ3LWEyNWQtNDFmOC04MWFiLTI5YTE2NGM5YTZmNABGAAAAAABPKgpqnlfYQ7BVC/BfH2XIBwCS0xhUjzMYSLVky9bw7LddAAAAjov5AACS0xhUjzMYSLVky9bw7LddAAADzoyxAAA="));
 		 
 		
+		 String b = "UsWdAIe4opTqcrX6~SrIMhBu5Gc9oZKEnnSDFRx9JwBINK8XTgnXUs2A3b7QmxDM9nRu8~mGsikVEoISLg.JTIHYRwv-Bp5ljIADLwUHv9iJAWo1delBOlW0Hd7nIVF0";
 		 
+		 System.out.println(DigestUtils.digestBase64Url(b,DigestUtils.Algorithm.SHA256));
 	}
 
 }