/**
* Run the query, sending the results directly to a JAXP Result object. This way of executing the
* query is most efficient in the case of queries that produce a single document (or parentless
* element) as their output, because it avoids constructing the result tree in memory: instead, it
* is piped straight to the serializer.
*
* @param env the dynamic query context
* @param result the destination for the results of the query. The query is effectively wrapped in
* a document{} constructor, so that the items in the result are concatenated to form a single
* document; this is then written to the requested Result destination, which may be (for
* example) a DOMResult, a SAXResult, or a StreamResult
* @param outputProperties Supplies serialization properties, in JAXP format, if the result is to
* be serialized. This parameter can be defaulted to null.
* @throws XPathException if the query fails.
*/
public void run(DynamicQueryContext env, Result result, Properties outputProperties)
throws XPathException {
if (isUpdating) {
throw new XPathException("Cannot call run() on an updating query");
}
Controller controller = newController();
initializeController(env, controller);
if (allowDocumentProjection) {
controller.setUseDocumentProjection(getPathMap());
}
Properties actualProperties = validateOutputProperties(controller, outputProperties);
controller.defineGlobalParameters();
XPathContextMajor context = initialContext(env, controller);
// In tracing/debugging mode, evaluate all the global variables first
TraceListener tracer = controller.getTraceListener();
if (tracer != null) {
controller.preEvaluateGlobals(context);
tracer.open();
}
context.openStackFrame(stackFrameMap);
boolean mustClose =
(result instanceof StreamResult && ((StreamResult) result).getOutputStream() == null);
context.changeOutputDestination(
actualProperties, result, true, Configuration.XQUERY, Validation.PRESERVE, null);
context.getReceiver().open();
// Run the query
try {
expression.process(context);
} catch (XPathException err) {
controller.reportFatalError(err);
throw err;
}
if (tracer != null) {
tracer.close();
}
context.getReceiver().close();
if (mustClose) {
OutputStream os = ((StreamResult) result).getOutputStream();
if (os != null) {
try {
os.close();
} catch (java.io.IOException err) {
throw new XPathException(err);
}
}
}
}
