Question

I am developing for mobile on Java 1.3 and don’t have enum type, so instead am using the Typesafe Enum Pattern. E.g.

public class DownloadEvent {

    //Download events
    public static final DownloadEvent DOWNLOAD_STARTED = new DownloadEvent("Download started");
    public static final DownloadEvent DOWNLOAD_COMPLETED = new DownloadEvent("Download completed");

    private String eventDescription;

    private DownloadEvent(String eventDescription){

        this.eventDescription = eventDescription;
    }

    public String toString(){
        return eventDescription;
    }
} 

The problem with this approach is that the compiler won’t allow classes inside switch statements e.g.

DownloadEvent event = getDownloadEvent(); //returns a download event

switch(event){
case DownloadEvent.DOWNLOAD_STARTED:
    //do some stuff
}

Is there any way around this? Or should I go back to using lists of int constants

Answer 1

You could give the DownloadEvent a type-property (for example an int) which you can retrieve with a getter, and use that property in your switch statement

DownloadEvent event = getDownloadEvent(); //returns a download event

switch(event.getType() ){
case DownloadEvent.DOWNLOAD_STARTED.getType():
    //do some stuff
}

But this is of course not as-nice as using an enum