Question

I have the following code:

    String serviceType;
    ServiceBrowser tmpBrowser;
    for (String playerName: players) {
        serviceType = "_" + playerName + "._tcp";
        tmpBrowser = BrowsersGenerator.getBrowser(serviceType);
        tmpBrowser.browse();
        System.out.println(tmpBrowser.getStatus());
    }       
    System.out.println(tmpBrowser.getStatus());

The compiler complains about the last line. It writes “variable tmpBrowser might not been initialized”. If I comment the last line the compile does not complain.

Answer 1

If there are no players, then the tmpBrowser won’t be initialized at any way. The compiler can’t predict if there are any players or not. Also, in contrary to fields (class/instance variables declared outside method blocks), local variables (declared inside method blocks) won’t be preinitialized with default values. You need to make the compiler happy by preinitializing it yourself:

ServiceBrowser tmpBrowser = null;

(don’t forget to do a nullcheck before getStatus(), else you may risk a NPE).