Working with Web Services - Beginning Java 7 - page 1074

XPathFactory xpf = XPathFactory.newInstance();
XPath xp = xpf.newXPath();
NodeList books = (NodeList) xp.evaluate("/book",
dom.getNode(),

XPathCon-

stants.NODESET);
String isbn = xp.evaluate("@isbn", books.item(0));
if (!library.containsKey(isbn))
throw new HTTPException(400);
String pubYear = xp.evaluate("@pubyear",

books.item(0));
String title = xp.evaluate("title",

books.item(0)).trim();
String publisher = xp.evaluate("publisher",

books.item(0)).trim();
NodeList authors = (NodeList)

xp.evaluate("author", books.item(0),

XPathCon-

stants.NODESET);
List<Author> auths = new ArrayList<>();
for (int i = 0; i < authors.getLength(); i++)
auths.add(new
Author(authors.item(i).getFirstChild()

.getNodeValue().trim()));
Book book = new Book(isbn, title, publisher, pub-
Year, auths);
library.put(isbn, book);
serialize();

}
catch (IOException | TransformerException e)
{

throw new HTTPException(500);

}
catch (XPathExpressionException xpee)
{

throw new HTTPException(400);