Reputation: 289

What does return do when used inside an if statement?

What does the return inside the if statements do in the following code?

public void startElement(String namespaceURI, String localName,String qName, 
                                         Attributes atts) throws SAXException
{
    depth++;
    if (localName.equals("channel"))
    {
        currentstate = 0;
        return;
    }
    if (localName.equals("image"))
    {
        // record our feed data - you temporarily stored it in the item :)
        _feed.setTitle(_item.getTitle());
        _feed.setPubDate(_item.getPubDate());
    }
    if (localName.equals("item"))
    {
        // create a new item
        _item = new RSSItem();
        return;
    }
    if (localName.equals("title"))
    {
        currentstate = RSS_TITLE;
        return;
    }
    if (localName.equals("description"))
    {
        currentstate = RSS_DESCRIPTION;
        return;
    }
    if (localName.equals("link"))
    {
        currentstate = RSS_LINK;
        return;
    }
    if (localName.equals("category"))
    {
        currentstate = RSS_CATEGORY;
        return;
    }
    if (localName.equals("pubDate"))
    {
        currentstate = RSS_PUBDATE;
        return;
    }
    // if you don't explicitly handle the element, make sure you don't wind 
           // up erroneously storing a newline or other bogus data into one of our 
           // existing elements
    currentstate = 0;
}

Does it takes us out of the if statement and proceeds to next statement or it takes us out of the method startElement?

Upvotes: 28

Answers (8)

Elliott Frisch

Reputation: 201429

The return will end the flow of the method, and is functionally identical to using a shorter else if chain like

/* if (localName.equals("channel")) {
    currentstate = 0; // This can be removed because it's the default below.
} else */ if (localName.equals("image")) {
    // record our feed data - you temporarily stored it in the item :)
    _feed.setTitle(_item.getTitle());
    _feed.setPubDate(_item.getPubDate());
} else if (localName.equals("item")) {
    // create a new item
    _item = new RSSItem();
} else if (localName.equals("title")) {
    currentstate = RSS_TITLE;
} else if (localName.equals("description")) {
    currentstate = RSS_DESCRIPTION;
} else if (localName.equals("link")) {
    currentstate = RSS_LINK;
} else  if (localName.equals("category")) {
    currentstate = RSS_CATEGORY;
} else if (localName.equals("pubDate")) {
    currentstate = RSS_PUBDATE;
} else {
    currentstate = 0;
}

Upvotes: 0

Alex

Reputation: 51

Yes. The return here will take the control out of method.

Upvotes: 3

Romeo

Reputation: 337

The return here is probably used in order to "improve" the performance of the method, so that other comparisons are not executed, once the needed scenario is performed.

However, it's not good practice to have multiple return points in a method.

As stated in my comments I'd try a different approach to achieve the flow of the code in question.

Upvotes: 0