Document doc = new Builder().build(new File("/tmp/test.xml")); Nodes results = XQueryUtil.xquery(doc, "//*:img/@src"); // Nodes results = XQueryUtil.xquery(doc, "//*:img/@src[matches(., '.jpg')]"); for (int i=0; i < results.size(); i++) { System.out.println("node "+i+": "+results.get(i).toXML()); //System.out.println("node "+i+": "+ XOMUtil.toPrettyXML(results.get(i))); } declare namespace atom = "http://www.w3.org/2005/Atom"; declare namespace xsd = "http://www.w3.org/2001/XMLSchema"; doc("http://www.tbray.org/ongoing/ongoing.atom")/atom:feed/atom:entry/atom:title Namespace declarations can be defined inline within the query prolog via declare namespace, and declare default element namespace directives, as described above. They can also be defined via the declareNamespace() methods and setDefaultElementNamespace() method of a {@link StaticQueryContext}. declare variable $i := 7; declare variable $j as xs:integer := 7; declare variable $math:pi as xs:double := 3.14159E0; declare variable $bookName := 'War and Peace';A query can access variable values via the standard
$varName syntax, as in return ($x, $math:pi) or /books/book[@name = $bookName]/author[@name = $authorName]. A query can declare external global variables, for example:
declare variable $foo as xs:string external; declare variable $size as xs:integer external; declare variable $myuri as xs:anyURI external; declare variable $mydoc as document-node() external; declare variable $myelem as element() external; declare variable $mynodes as node()* external;External global variables can be bound and passed to the query as follows:
Map vars = new HashMap(); vars.put("foo", "hello world"); vars.put("size", new Integer(99)); vars.put("myuri", "http://www.w3.org/2001/XMLSchema"); vars.put("mydoc", new Document(new Element("xyz"))); vars.put("myelem", new Element("abc")); vars.put("mynodes", new Node[] {new Document(new Element("elem1")), new Element("elem2"))}); vars.put("mydocs", new Node[] { new Builder().build(new File("samples/data/articles.xml")), new Builder().build(new File("samples/data/p2pio.xml")) }); String query = "for $d in $mydocs return $size * count($d)"; Nodes results = new XQuery(query, null).execute(doc, null, vars).toNodes(); new ResultSequenceSerializer().write(results, System.out); fn:matches, fn:replace, and fn:tokenize functions. For example: string-length('hello world'); A query can employ user defined functions, for example:
declare namespace ipo = "http://www.example.com/IPO"; declare function local:total-price( $i as element(item)* ) as xs:double { let $subtotals := for $s in $i return $s/quantity * $s/USPrice return sum($subtotals) }; for $p in doc("ipo.xml")/ipo:purchaseOrder where $p/shipTo/name="Helen Zoe" and $p/@orderDate = xs:date("1999-12-01") return local:total-price($p//item) Custom extension functions written in Java can be defined and used as explained in the Saxon Extensibility Functions documentation. For example, here is query that outputs the square root of a number via a method in java.lang.Math, as well as calls static methods and constructors of java.lang.String, java.util.Date as well as other extension functions. declare namespace exslt-math = "http://exslt.org/math"; declare namespace math = "java:java.lang.Math"; declare namespace date = "java:java.util.Date"; declare namespace string = "java:java.lang.String"; declare namespace saxon = "http://saxon.sf.net/"; declare variable $query := string(doc("query.xml")/queries/query[1]); ( exslt-math:sin(3.14) math:sqrt(16), math:pow(2,16), string:toUpperCase("hello"), date:new(), (: print current date :) date:getTime(date:new()) (: print current date in milliseconds :) saxon:eval(saxon:expression($query)) (: run a dynamically constructed query :) ) (: file modules/factorial.xq :) module namespace factorial = "http://example.com/factorial"; declare function factorial:fact($i as xs:integer) as xs:integer { if ($i <= 1) then 1 else $i * factorial:fact($i - 1) }; (: file main.xq :) import module namespace factorial = "http://example.com/factorial" at "modules/factorial.xq"; factorial:fact(4) [hoschek /Users/hoschek/unix/devel/nux] fire-xquery main.xq <atomic-value xsi:type="xs:integer" xmlns="http://dsd.lbl.gov/nux" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">24</atomic-value> doc() function can be defined in the constructor of this class. Other miscellaneous options can be made available to the query by calling configuration methods on a {@link DynamicQueryContext} (per execution),or on the configuration object of a {@link StaticQueryContext} (per query). | |