Avoid using HashSet with java.net.URL - causing significant slowdown

[czpilar]

ConfigurationBuilder class uses HashSet with java.net.URL which causes significant application slowdown.

public ConfigurationBuilder setUrls(Collection<URL> urls) {
		this.urls = new HashSet<>(urls);
        return this;
}

According to https://rules.sonarsource.com/java/RSPEC-2112

The equals and hashCode methods of java.net.URL both may trigger a name service (usually DNS) lookup to resolve the host name or IP address. Depending on the configuration, and network status, that can take a long time. URI on the other hand makes no such calls and should be used instead unless the specific URL functionality is required.

In general it is better to use the URI class until access to the resource is actually needed, at which point you can just convert the URI to a URL using URI.toURL().