Conditional operator in concatenated string

Question

I\'d like know why the following program throws a NPE

public static void main(String[] args) {
    Integer testInteger = null;
    String test = \"test\" + t         


        

Answer 1

I believe you need to add the parenthesis. Here is a working example which produces "http://localhost:8080/catalog/rest"

public static String getServiceBaseURL(String protocol, int port, String hostUrl, String baseUrl) {
    return protocol + "://" + hostUrl + ((port == 80 || port == 443) ? "" : ":" + port) + baseUrl;
}