Is there a way to automatically initialize a variable if null

Question

I have this code in Java:

String foo = request.getParameter("bar");
if (foo == null) { 
    foo = ""; 
}

There are multiple values checked this way. In other languages I would probably be able to do something like this:

String foo = request.getParameter("bar") || "";

I was really just wondering if there is an equivalent in Java.

Answer 1

If you use java 8, you can probably go with something like this:

Optional.ofNullable(request.getParameter("bar")).orElse("")

If you don't use java 8, you have the option to use the Optional from Google Guava. Which offers similar API. For ex.

Optional.fromNullable(request.getParameter("bar")).or("")

Both of these allow specifying a function to create the alternate value as well.

If you just want to go old-school, create a method like:

static String emptyIfNull(String value) {
    if (value == null) return "";
    else return value;
}

emptyIfNull(request.getParameter("bar"))