I return empty collections vs. null whenever possible. I switch between two methods for doing so using java.util.Collections:
return Collections.EMPTY_LIST;
return Collections.emptyList();
where emptyList()
is supposed to be type-safe. But I recently discovered:
return Collections.<ComplexObject> emptyList();
return Collections.<ComplexObject> singletonList(new ComplexObject());
etc.
I see this method in Eclipse Package Explorer:
<clinit> () : void
but I don't see how this is done in the source code (1.5). How is this magic tomfoolerie happening!!
EDIT: How is the static Generic type accomplished?
EDIT: How is the static Generic type accomplished?
http://www.docjar.com/html/api/java/util/Collections.java.html
public class Collections {
...
public static final List EMPTY_LIST = new EmptyList<Object>();
...
public static final <T> List<T> emptyList() {
return (List<T>) EMPTY_LIST;
}
...
}
You can see the link for the implementation of the EmptyList class if you're curious, but for your question, it doesn't matter.