Add Tag creation usecase

2-Application/src/main/java/link/LinkUseCase.java

@@ -2,6 +2,7 @@ package link;
 
 import category.CategoryName;
 import category.CategoryRepository;
+import exeptions.URLIsNotReachable;
 import tag.TaggingUseCase;
 import user.Username;
 
@@ -27,7 +28,9 @@ public class LinkUseCase {
 
 	public void addLink(LinkUrl url, Set<CategoryName> categoryNames, Username creator) {
 
-		OnlineCheck.of(url);
+		if (!OnlineCheck.isReachable(url)) {
+			throw new URLIsNotReachable("The url " + url + " does not seem online. Check if it is correct and you have internet access.");
+		}
 
 		var categoryIds = categoryNames.stream().map(categoryRepository::getIdByName).collect(Collectors.toSet());
 

3-Domain/src/main/java/exeptions/URLIsNotReachable.java

@@ -0,0 +1,8 @@
+package exeptions;
+
+public class URLIsNotReachable extends  RuntimeException {
+
+	public URLIsNotReachable(String message) {
+		super(message);
+	}
+}

3-Domain/src/main/java/link/OnlineCheck.java

@@ -5,7 +5,7 @@ import java.net.HttpURLConnection;
 
 public class OnlineCheck {
 
-	static Boolean of(LinkUrl url) {
+	static Boolean isReachable(LinkUrl url) {
 		int responseCode = getResponseCode(url);
 		return (responseCode < 400 || responseCode == 401 || responseCode == 403);
 	}