/**
* Statically analyze a query for various properties.
*
* @param query the query to analyze
* @param params parameters for the query; if necessary parameters are left out they will be
* listed as required variables in the analysis
* @return a query analysis facet
*/
public QueryAnalysis analyze(String query, Object... params) {
if (presub) query = presub(query, params);
long t1 = System.currentTimeMillis(), t2 = 0, t3 = 0;
DBBroker broker = null;
try {
broker = db.acquireBroker();
prepareContext(broker);
final org.exist.source.Source source = buildQuerySource(query, params, "analyze");
final XQuery xquery = broker.getXQueryService();
final XQueryPool pool = xquery.getXQueryPool();
CompiledXQuery compiledQuery = pool.borrowCompiledXQuery(broker, source);
try {
AnalysisXQueryContext context;
if (compiledQuery == null) {
context = new AnalysisXQueryContext(broker, AccessContext.INTERNAL_PREFIX_LOOKUP);
buildXQueryStaticContext(context, false);
buildXQueryDynamicContext(context, params, null, false);
t2 = System.currentTimeMillis();
compiledQuery = xquery.compile(context, source);
t3 = System.currentTimeMillis();
} else {
context = (AnalysisXQueryContext) compiledQuery.getContext();
t2 = System.currentTimeMillis();
}
return new QueryAnalysis(
compiledQuery,
Collections.unmodifiableSet(context.requiredVariables),
Collections.unmodifiableSet(context.requiredFunctions));
} finally {
if (compiledQuery != null) pool.returnCompiledXQuery(source, compiledQuery);
}
} catch (XPathException e) {
LOG.warn(
"query compilation failed -- "
+ query
+ " -- "
+ (params == null ? "" : " with params " + Arrays.asList(params))
+ (bindings.isEmpty() ? "" : " and bindings " + bindings));
throw new DatabaseException("failed to compile query", e);
} catch (IOException e) {
throw new DatabaseException("unexpected exception", e);
} catch (PermissionDeniedException e) {
throw new DatabaseException("permission denied", e);
} finally {
db.releaseBroker(broker);
STATS.update(query, t1, t2, t3, 0, System.currentTimeMillis());
}
}
/**
* Convert the given object into a value appropriate for being defined as the value of a variable
* in an XQuery. This will extract a sequence out of all database objects, convert collections and
* arrays into sequences recursively, convert <code>null</code> into an empty sequence, and pass
* other objects through untouched. Convertible objects that are defined in the JDK will be
* automatically converted by eXist.
*
* @see org.exist.xquery.XPathUtil#javaObjectToXPath(Object, XQueryContext, boolean)
* @param o the object to convert to a database value
* @return the converted value, ready for assignment to an XQuery variable
*/
@SuppressWarnings("unchecked")
private Object convertValue(Object o) {
if (o == null) return Collections.emptyList();
if (o instanceof Resource) {
try {
return ((Resource) o).convertToSequence();
} catch (UnsupportedOperationException e) {
return o;
}
}
List<Object> list = null;
if (o instanceof Collection) list = new ArrayList<Object>((Collection) o);
else if (o instanceof Object[]) list = new ArrayList<Object>(Arrays.asList((Object[]) o));
if (list != null) {
for (ListIterator<Object> it = list.listIterator(); it.hasNext(); ) {
it.set(convertValue(it.next()));
}
return list;
}
return DataUtils.toXMLObject(o);
}
ItemList executeQuery(String query, WrapperFactory wrapperFactory, Object[] params) {
long t1 = System.currentTimeMillis(), t2 = 0, t3 = 0, t4 = 0;
if (presub) query = presub(query, params);
DBBroker broker = null;
try {
broker = db.acquireBroker();
prepareContext(broker);
if (overrideDocs != null) docs = overrideDocs;
final org.exist.source.Source source = buildQuerySource(query, params, "execute");
final XQuery xquery = broker.getXQueryService();
final XQueryPool pool = xquery.getXQueryPool();
CompiledXQuery compiledQuery = pool.borrowCompiledXQuery(broker, source);
MutableDocumentSet docsToLock = new DefaultDocumentSet();
if (docs != null) docsToLock.addAll(docs);
if (base != null) docsToLock.addAll(base.getDocumentSet());
try {
XQueryContext context;
if (compiledQuery == null) {
context = xquery.newContext(AccessContext.INTERNAL_PREFIX_LOOKUP);
buildXQueryStaticContext(context, true);
} else {
context = compiledQuery.getContext();
// static context already set
}
buildXQueryDynamicContext(context, params, docsToLock, true);
t2 = System.currentTimeMillis();
if (compiledQuery == null) {
compiledQuery = xquery.compile(context, source);
t3 = System.currentTimeMillis();
}
docsToLock.lock(broker, false, false);
try {
return new ItemList(
xquery.execute(wrap(compiledQuery, wrapperFactory, context), base),
namespaceBindings.extend(),
db);
} finally {
docsToLock.unlock(false);
t4 = System.currentTimeMillis();
}
} finally {
if (compiledQuery != null) pool.returnCompiledXQuery(source, compiledQuery);
}
} catch (XPathException e) {
LOG.debug(
"query execution failed -- "
+ query
+ " -- "
+ (params == null ? "" : " with params " + Arrays.asList(params))
+ (bindings.isEmpty() ? "" : " and bindings " + bindings));
throw new DatabaseException("failed to execute query", e);
} catch (IOException e) {
throw new DatabaseException("unexpected exception", e);
} catch (LockException e) {
throw new DatabaseException("deadlock", e);
} catch (PermissionDeniedException e) {
throw new DatabaseException("permission denied", e);
} finally {
db.releaseBroker(broker);
STATS.update(query, t1, t2, t3, t4, System.currentTimeMillis());
}
}
/**
* Limit the root documents accessible to the query to the given list, overriding the any set
* derived from the query's context. The query will still be able to access other documents
* through bound variables or by naming them directly, though.
*
* @param rootDocs the list of root documents to limit the query to
* @return this service, to chain calls
*/
public QueryService limitRootDocuments(XMLDocument... rootDocs) {
return limitRootDocuments(Arrays.asList(rootDocs));
}