Oracle has released the final version of Java Specification Request (JSR) 225, XQuery API for Java™ (XQJ). There's also a reference implementation and technical compatibility kit. As JDBC is to SQL, XQJ is to XQuery.
The following sample Java code is meant to convey a first look and feel of the style and usage of the XQJ API. It is by no means exhaustive or complete; e.g., no error handling is shown and it is assumed that xqds is an XQDataSource object representing a given data source. It illustrates the basic steps that an application would perform to execute an XQuery expression at a given XQuery implementation.
// establish a connection to the XQuery engine XQConnection conn = xqds.getConnection(); // create an expression object that is later used // to execute an XQuery expression XQExpression expr = conn.createExpression(); // the XQuery expression to be executed String es = "for $n in fn:doc('catalog.xml')//item " + "return fn:data($n/name)"; // execute the XQuery expression XQResultSequence result = expr.executeQuery(es); // process the result (sequence) iteratively while (result.next()) { // retrieve the current item of the sequence as a String String str = result.getAtomicValue(); System.out.println("Product name: " + str); } // free all resources allocated for the result result.close(); // free all resources allocated for the expression expr.close(); // free all resources allocated for the connection conn.close();
On a side note, kudos to the spec authors for putting this simple example in the spec right up front. Something like this would help a lot of other JSRs.
