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Sat, 29 Jan 2005

Quotes Manager Project -- Day 11

An ongoing pet project blog...

I'm back to green. I needed a CDataSection rather than an ordinary Element. I broke the tests because a CDataSection wraps the text with <![CDATA[]]>. Here's the code:

    public void newQuote(Quote quote) {
        Node root = document.getDocumentElement();
        Node quoteNode = document.createElement("quote");

        Node textNode = document.createElement("text");
        Node textSection = document.createCDATASection(quote.text);
        textNode.appendChild(textSection);
        quoteNode.appendChild(textNode);

        Node sourceNode = document.createElement("source");
        Attr sourceIsbn = document.createAttribute("isbn");
        sourceIsbn.setValue(quote.source.isbn);
        sourceNode.getAttributes().setNamedItem(sourceIsbn);
        sourceNode.setTextContent(quote.source.title);
        quoteNode.appendChild(sourceNode);

        for (Person author : quote.authors) {
            Attr authorUrl = document.createAttribute("url");
            authorUrl.setValue(author.url);
            Node authorNode = document.createElement("author");
            authorNode.getAttributes().setNamedItem(authorUrl);

            Node authorFirst = document.createElement("first");
            authorFirst.setTextContent(author.firstName);
            authorNode.appendChild(authorFirst);

            Node authorLast = document.createElement("last");
            authorLast.setTextContent(author.lastName);
            authorNode.appendChild(authorLast);

            quoteNode.appendChild(authorNode);
        }

        root.appendChild(quoteNode);
    }

And here's the latest test...

    public void testShouldWriteXmlWhenGivenNewQuoteWithPageNumber() throws Exception {
        String text = "The major problems of our work are not so much <i>technological</i> as <i>sociological</i> in nature.";
        String isbn = "0932633439";
        String title = "Peopleware: Productive Projects and Teams";
        String page = "4";
        String firstName1 = "Tom";
        String lastName1 = "DeMarco";
        String url1 = "http://www.systemsguild.com/GuildSite/TDM/Tom_DeMarco.html";
        String firstName2 = "Timothy";
        String lastName2 = "Lister";
        String url2 = "http://www.cutter.com/consultants/tlbio.html";
        Collection<Person> authors = new ArrayList<Person>(2);
        authors.add(new Person(firstName1, lastName1, url1));
        authors.add(new Person(firstName2, lastName2, url2));
        Quote quote = new Quote(text, new Source(title, page, isbn), authors, null);

        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();
        Document document = builder.parse("stub.xml");

        assertEquals(0, document.getElementsByTagName("quote").getLength());

        Manager manager = new XmlQuoteManager(document);
        manager.newQuote(quote);

        assertEquals(1, document.getElementsByTagName("quote").getLength());

        String textContent = documentToText(document);
        assertTrue(-1 != textContent.indexOf("<text><![CDATA[" + text + "]]></text>"));
//        assertTrue(-1 != textContent.indexOf("<source isbn=\""+ isbn + "\" page=\"" + page + "\">" + title + "</source>"));
//        assertTrue(-1 != textContent.indexOf("<author url=\""+ url1 + "\"><first>" + firstName1 + "</first><last>" + lastName1 + "</last></author>"));
//        assertTrue(-1 != textContent.indexOf("<author url=\""+ url2 + "\"><first>" + firstName2 + "</first><last>" + lastName2 + "</last></author>"));
    }

I'll uncomment those tests and see where I am. Arg, they're failing on the next line. Something to do with the source, it's missing a page. Oh, there's a good reason for that, I never coded it. This is why I write tests first.

So I added the page attribute, but then my other test broke because it doesn't have a page. Time for a handy-dandy if statement. Ahhh, back to green. Here's the if block:

        if (quote.source.page != null && !quote.source.page.trim().equals("")) {
            Attr sourcePage = document.createAttribute("page");
            sourcePage.setValue(quote.source.page);
            sourceNode.getAttributes().setNamedItem(sourcePage);
        }

I need a test with a quoter.

    public void testShouldWriteXmlWhenGivenNewQuoteWithQuoter() throws Exception {
        String text = "To be able to understand when the rules don't apply, you need to completely understand when they do.";
        String isbn = "0201760436";
        String title = "Agile Software Development Ecosystems";
        String page = "31";
        String quoterFirstName = "Bob";
        String quoterLastName = "Charette";
        String quoterUrl = "http://www.cutter.com/consultants/charetter.html";
        Person quoter = new Person(quoterFirstName, quoterLastName, quoterUrl);
        String firstName = "Jim";
        String lastName = "Highsmith";
        String url = "http://www.adaptivesd.com/";
        Collection<Person> authors = new ArrayList<Person>(1);
        authors.add(new Person(firstName, lastName, url));
        Quote quote = new Quote(text, new Source(title, page, isbn), authors, quoter);

        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();
        Document document = builder.parse("stub.xml");

        assertEquals(0, document.getElementsByTagName("quote").getLength());

        Manager manager = new XmlQuoteManager(document);
        manager.newQuote(quote);

        assertEquals(1, document.getElementsByTagName("quote").getLength());

        String textContent = documentToText(document);
        assertTrue(-1 != textContent.indexOf("<text><![CDATA[" + text + "]]></text>"));
        assertTrue(-1 != textContent.indexOf("<source isbn=\""+ isbn + "\" page=\"" + page + "\">" + title + "</source>"));
        assertTrue(-1 != textContent.indexOf("<author url=\""+ url + "\"><first>" + firstName + "</first><last>" + lastName + "</last></author>"));
        assertTrue(-1 != textContent.indexOf("<quoter url=\""+ quoterUrl + "\"><first>" + quoterFirstName + "</first><last>" + quoterLastName + "</last></quoter>"));
    }

This fails where I expected, on the last assert. I'll put in the quoter code on the way home. We just pulled into Chicago...

Back to green. I basically just copied and pasted the body of the author loop and after a couple SHIFT-F6's the variables had the appropriate names.

    public void newQuote(Quote quote) {
        Node root = document.getDocumentElement();
        Node quoteNode = document.createElement("quote");

        Node textNode = document.createElement("text");
        Node textSection = document.createCDATASection(quote.text);
        textNode.appendChild(textSection);
        quoteNode.appendChild(textNode);

        Node sourceNode = document.createElement("source");
        Attr sourceIsbn = document.createAttribute("isbn");
        sourceIsbn.setValue(quote.source.isbn);
        sourceNode.getAttributes().setNamedItem(sourceIsbn);

        if (quote.source.page != null && !quote.source.page.trim().equals("")) {
            Attr sourcePage = document.createAttribute("page");
            sourcePage.setValue(quote.source.page);
            sourceNode.getAttributes().setNamedItem(sourcePage);
        }
        sourceNode.setTextContent(quote.source.title);
        quoteNode.appendChild(sourceNode);

        for (Person author : quote.authors) {
            Attr authorUrl = document.createAttribute("url");
            authorUrl.setValue(author.url);
            Node authorNode = document.createElement("author");
            authorNode.getAttributes().setNamedItem(authorUrl);

            Node authorFirst = document.createElement("first");
            authorFirst.setTextContent(author.firstName);
            authorNode.appendChild(authorFirst);

            Node authorLast = document.createElement("last");
            authorLast.setTextContent(author.lastName);
            authorNode.appendChild(authorLast);

            quoteNode.appendChild(authorNode);
        }

        if (quote.quoter != null) {
            Attr quoterUrl = document.createAttribute("url");
            quoterUrl.setValue(quote.quoter.url);
            Node quoterNode = document.createElement("quoter");
            quoterNode.getAttributes().setNamedItem(quoterUrl);

            Node quoterFirst = document.createElement("first");
            quoterFirst.setTextContent(quote.quoter.firstName);
            quoterNode.appendChild(quoterFirst);

            Node quoterLast = document.createElement("last");
            quoterLast.setTextContent(quote.quoter.lastName);
            quoterNode.appendChild(quoterLast);

            quoteNode.appendChild(quoterNode);
        }

        root.appendChild(quoteNode);
    }

There's nothing that drives me crazier than developers who copy and paste code without refactoring it out. So it's time to refactor this monsterous method. After a series of CTRL-ALT-M's and CTRL-ALT-N's, otherwise known as extract method and inline variable, the method looks a lot nicer.

    public void newQuote(Quote quote) {
        Node quoteNode = document.createElement("quote");

        quoteNode.appendChild( createTextNode(quote) );
        quoteNode.appendChild( createSourceNode(quote) );

        for (Person author : quote.authors)
            quoteNode.appendChild( createAuthorNode(author) );

        if (quote.quoter != null)
            quoteNode.appendChild( createQuoterNode(quote) );

        document.getDocumentElement().appendChild( quoteNode );
    }

The tests are still green. There is duplication between the createQuoterNode and createAuthorNode. Let's get rid of that ASAP. I'll start by seeing what happens if I use the createAuthorNode rather than the createQuoterNode.

    public void newQuote(Quote quote) {
        Node quoteNode = document.createElement("quote");

        quoteNode.appendChild( createTextNode(quote) );
        quoteNode.appendChild( createSourceNode(quote) );

        for (Person author : quote.authors)
            quoteNode.appendChild( createAuthorNode(author) );

        if (quote.quoter != null)
            quoteNode.appendChild( createAuthorNode(quote.quoter) );

        document.getDocumentElement().appendChild( quoteNode );
    }

That breaks the quoter test because now the quoter is showing up as an author. I introduce parameter (CTRL-ALT-P) on tag name, make sure the quoter code is passing in "quoter" and rename method (SHIFT-F6). Voila! Back to green, and IDEA tells me I have dead code (createQuoterNode) I can delete. So I do (I really love that feeling).

Here's the current state of the method:

    public void newQuote(Quote quote) {
        Node quoteNode = document.createElement("quote");

        quoteNode.appendChild( createTextNode(quote) );
        quoteNode.appendChild( createSourceNode(quote) );

        for (Person author : quote.authors)
            quoteNode.appendChild( createPersonNode(author, "author") );

        if (quote.quoter != null)
            quoteNode.appendChild( createPersonNode(quote.quoter, "quoter") );

        document.getDocumentElement().appendChild( quoteNode );
    }

I should find some other permutations to test before moving on. Like authors without URLs or sources without ISBNs. But I won't bore you with them now.

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