Include the invalid URL value in the message

This helps to quickly track down configuration problems, especially in systems that generate the config rather than depend on flat files.

Author: kryger

spring-boot-admin-server/src/main/java/de/codecentric/boot/admin/registry/ApplicationRegistry.java

@@ -58,13 +58,13 @@ public Application register(Application application) {
 Assert.notNull(application, "Application must not be null");
 Assert.hasText(application.getName(), "Name must not be null");
 Assert.hasText(application.getHealthUrl(), "Health-URL must not be null");
-Assert.isTrue(checkUrl(application.getHealthUrl()), "Health-URL is not valid");
+Assert.isTrue(checkUrl(application.getHealthUrl()), "Health-URL is not valid: " + application.getHealthUrl());
 Assert.isTrue(
 StringUtils.isEmpty(application.getManagementUrl())
-|| checkUrl(application.getManagementUrl()), "URL is not valid");
+|| checkUrl(application.getManagementUrl()), "URL is not valid: " + application.getManagementUrl());
 Assert.isTrue(
 StringUtils.isEmpty(application.getServiceUrl())
-|| checkUrl(application.getServiceUrl()), "URL is not valid");
+|| checkUrl(application.getServiceUrl()), "URL is not valid: " + application.getServiceUrl());
 
 String applicationId = generator.generateId(application);
 Assert.notNull(applicationId, "ID must not be null");