public static URL checkValidURL(String url) {
		try {
			return new URL(url);
		} catch (Exception e) {
			throw new IllegalArgumentException("Url " + url + "should be valid", e);
		}
	}
Ensures that given url is valid URL.

@param url url String
@return converted url
ngrinder-core/src/main/java/org/ngrinder/common/util/Preconditions.java