Improved API, added checks, added tests; doesn't currently run tho

src/main/java/com/cringe_studios/cringe_authenticator_library/OTP.java

@@ -45,10 +45,10 @@ public abstract class OTP {
 	 * @param counter REQUIRED if HOTP, otherwise meaningless. The initial counter for HOTP (eg 21, if user reloaded counter 21 times)
 	 * @param periodInSeconds OPTIONAL (default 30) for TOTP, the refresh rate of the TOTP
 	 * @param checksum OPTIONAL: appends a checksum digit to the end of the string
-	 * @return returns a valid OTP object or null, which can be used to create a new OTP pin
+	 * @return returns a valid OTP object, which can be used to create a new OTP pin
 	 */ 
 	public static OTP createNewOTP(OTPType type, String secret, OTPAlgorithm algorithm, int digits, long counter, long periodInSeconds, boolean checksum) throws OTPException{
-		if(type == null) return null;
+		if(type == null) throw new OTPException("No OTP Type given!");
 		return type.instance(secret, algorithm, digits, counter, periodInSeconds, checksum);
 	}
 	

src/main/java/com/cringe_studios/cringe_authenticator_library/OTPException.java

@@ -1,6 +1,6 @@
 package com.cringe_studios.cringe_authenticator_library;
 
-public class OTPException extends RuntimeException {
+public class OTPException extends Exception {
 
 	private static final long serialVersionUID = 4635395862998258574L;
 

src/main/java/com/cringe_studios/cringe_authenticator_library/OTPType.java

@@ -16,15 +16,15 @@ public enum OTPType {
 		return friendlyName;
 	}
 
-	public OTP instance(String secret, OTPAlgorithm algorithm, int digits, long counter, long periodInSeconds, boolean checksum) {
+	public OTP instance(String secret, OTPAlgorithm algorithm, int digits, long counter, long periodInSeconds, boolean checksum) throws OTPException {
 		if(/*type == null ||*/ secret == null || secret.length() == 0/*|| counter < 0*/) {
-			return null;
+			throw new OTPException("Invalid Secret!");
 		}
 		
 		try {
 			Base32.decode(secret);
 		}catch (IllegalArgumentException e) {
-			throw new OTPException("Your secret is invalid! Please rescan the code!", e);
+			throw new OTPException("Invalid Secret!", e);
 		}
 		
 		switch(this) {
@@ -32,7 +32,7 @@ public enum OTPType {
 				return new com.cringe_studios.cringe_authenticator_library.impl.HOTP(secret, algorithm, digits, counter, periodInSeconds, checksum);
 			case TOTP:
 				return new com.cringe_studios.cringe_authenticator_library.impl.TOTP(secret, algorithm, digits, counter, periodInSeconds, checksum);
-			default: return null;
+			default: throw new OTPException("No OTP Type given!"); //Respect, if you run this code
 		}	
 	}
 }

src/test/java/test/OTPTest.java

@@ -2,6 +2,7 @@ package test;
 
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import java.math.BigInteger;
@@ -64,6 +65,11 @@ public class OTPTest {
 		
 		OTP testOTP4 = OTP.createNewOTP(OTPType.HOTP, base32secret, OTPAlgorithm.SHA512, 10, 0, 0, false);
 		assertDoesNotThrow(() -> testOTP4.getPin());
+		
+		assertDoesNotThrow(() -> {
+			OTP testOTP5 = OTP.createNewOTP(OTPType.HOTP, "", OTPAlgorithm.SHA1, 8, 0, 0, false);
+			assertNotNull(testOTP5);
+		});
 	}
 
 	private static byte[] hexStr2Bytes(String hex) {