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1
12
13 package org.xquark.mediator.plan;
14
15 import java.util.ArrayList  ;
16
17 import org.apache.commons.logging.Log;
18 import org.apache.commons.logging.LogFactory;
19 import org.xml.sax.ErrorHandler ;
20 import org.xml.sax.SAXException ;
21 import org.xml.sax.SAXParseException ;
22 import org.xquark.mediator.DOMUtils.GetUnknownPathsVisitor;
23 import org.xquark.mediator.DOMUtils.SAX2DOM;
24 import org.xquark.mediator.DOMUtils.Tuple;
25 import org.xquark.mediator.decomposer.Utils;
26 import org.xquark.mediator.runtime.MediatorException;
27 import org.xquark.schema.validation.PSVInfoSetProvider;
28 import org.xquark.schema.validation.SchemaValidationContext;
29 import org.xquark.schema.validation.ValidatingSchemaHandler;
30 import org.xquark.util.NamespaceContextStack;
31 import org.xquark.xml.xdbc.*;
32 import org.xquark.xquery.parser.*;
33 import org.xquark.xquery.typing.QType;
34
35 public class OpSource extends ZeroOp {
36 private static final String RCSRevision = "$Revision: 1.51 $";
40
41 private static final String RCSName = "$Name: $";
42
43 private PreparedXMLStatement preparedStatement = null;
48
49 private ArrayList externalVariables = null;
50
51 private String requestStr = null;
52
53 private String preparedRequestStr = null;
54
55 private String source = null;
56
57 private boolean cannotBePrepared = false;
58
59
65 public OpSource(ExecutionPlan plan, XQueryExpression expression, ArrayList origpaths, String source, boolean hasIdentifier) throws MediatorException {
66 super(plan, expression);
67 try {
68 for (int i = 0; i < origpaths.size(); i++) {
69 addPath((XQueryExpression) ((XQueryExpression) origpaths.get(i)).clone());
70 }
71 } catch (CloneNotSupportedException cnse) {
72 }
73 this.source = source;
75 this.size = this.getPaths().size();
76 if (hasIdentifier)
77 this.idsize = 1;
78 if (source == null)
79 throw new MediatorException("AlgSource: no source !");
80 createRequestString();
82 GetUnknownPathsVisitor gupv = new GetUnknownPathsVisitor(getSchemaManager(), getTypeVisitor());
83 try {
84 expression.accept(gupv);
85 } catch (XQueryException xqe) {
86 throw new MediatorException(xqe.getMessage());
87 }
88 externalVariables = gupv.getNewVariables();
89 if (externalVariables != null)
91 for (int i = 0; i < externalVariables.size(); i++) {
92 Variable vari = (Variable) externalVariables.get(i);
93 QType qtypei = vari.getQType();
94 if (qtypei.isMultiple()) {
95 cannotBePrepared = true;
96 break;
97 }
98 }
99 }
100
101
105 public void accept(OperatorVisitor visitor) throws MediatorException {
106 visitor.visit(this);
107 }
108
109
115 protected ResultSet getResultSet(DynamicContext context) throws MediatorException {
116 ResultSet resultset = null;
117 if (!cannotBePrepared)
118 if (preparedRequestStr != null) {
119 try {
120 preparedStatement = context.getPreparedXMLStatement(this, source, preparedRequestStr);
121 } catch (XMLDBCException xe) {
122 preparedRequestStr = null;
123 preparedStatement = null;
124 throw new MediatorException(xe.getMessage(), xe);
125 }
126 }
127 if (preparedStatement != null)
128 resultset = new SourceResultSet(this, context, preparedStatement);
129 else {
130 XMLConnection connection = null;
131 connection = context.getConnection().getSubConnectionByName(source);
132 if (connection == null)
133 throw new MediatorException("AlgSource: couldn't established connection to " + source);
134 resultset = new SourceResultSet(this, context, connection);
135 }
136 return resultset;
137 }
138
139
142 public ArrayList getSources() {
143 if (sources == null) {
144 sources = new ArrayList ();
145 sources.add(source);
146 }
147 return sources;
148 }
149
150 public String getSourceName() {
151 return source;
152 }
153
154 public void setPrepared() throws MediatorException {
155 if (!cannotBePrepared || prepared)
156 return;
157 StringBuffer sbvars = new StringBuffer ();
159 sbvars.append(requestStr);
160 if (externalVariables != null && !externalVariables.isEmpty()) {
161 plan.appendExternalVariables(sbvars, externalVariables);
162 if (sbvars.length() == 0) {
163 preparedStatement = null;
164 prepared = false;
165 return;
166 }
167 }
168 sbvars.append(expression.getStringValue(plan.getModule().getDeclarations()));
170 preparedRequestStr = sbvars.toString();
171 prepared = true;
172 }
173
174 private void createRequestString() {
176 if (requestStr == null) {
177 StringBuffer sb = new StringBuffer ();
178 sb.append("declare validation preserve;\n");
179 String tmpstr = plan.getDeclarations();
180 if (tmpstr != null)
181 sb.append(tmpstr);
182 sb.append("declare namespace xsi = \"http://www.w3.org/2001/XMLSchema-instance\";\n");
183 requestStr = sb.toString();
184 }
185 }
186
187 public ArrayList getExternalVariables() {
188 return externalVariables;
189 }
190
191 public String getRequestStr() {
192 return requestStr;
193 }
194
195 public String getPreparedRequestStr() {
196 return preparedRequestStr;
197 }
198
199 public String toCompleteString(int indent) {
203 StringBuffer buf = new StringBuffer ();
204 buf.append(Utils.makeIndent(indent) + "<" + getClass().getName() + " isLet=\"" + islet + "\" valueDepends=\"" + valueDepends + "\" whereDepends=\"" + whereDepends + "\">\n");
205 buf.append(Utils.makeIndent(indent + 1) + "<Expression>\n");
206 buf.append(Utils.makeIndent(indent + 2) + expression + "\n");
207 buf.append(Utils.makeIndent(indent + 1) + "</Expression>\n");
208 buf.append(Utils.makeIndent(indent + 1) + "<Source>" + source + "</Source>\n");
209 if (paths != null) {
217 buf.append(Utils.makeIndent(indent + 1) + "<Paths>\n");
218 for (int i = 0; i < paths.size(); i++) {
219 buf.append(Utils.makeIndent(indent + 2) + "<Path>" + paths.get(i) + "</Path>\n");
220 }
221 buf.append(Utils.makeIndent(indent + 1) + "</Paths>\n");
222 }
223 buf.append(Utils.makeIndent(indent) + "</" + getClass().getName() + ">\n");
224 return buf.toString();
225 }
226
227 }
228
229 class SourceResultSet extends ZeroResultSet {
230 private static final String RCSRevision = "$Revision: 1.51 $";
234
235 private static final String RCSName = "$Name: $";
236
237 private static Log log = LogFactory.getLog(SourceResultSet.class);
238
239 private XMLStatement statement = null;
243
244 private XMLResultSet resultset = null;
245
246 private PSVInfoSetProvider psvip = null;
247
248 private ValidatingSchemaHandler vsh = null;
250
251 private SAX2DOM thandler = null;
252
253
259 public SourceResultSet(OpSource operator, DynamicContext context, XMLConnection connection) throws MediatorException {
260 super(operator, context);
261 try {
262 statement = connection.createStatement();
263 } catch (XMLDBCException xe) {
264 throw new MediatorException(xe.getMessage(), xe);
265 }
266
267 StringBuffer sb = new StringBuffer ();
268
269 sb.append(operator.getRequestStr());
270
271 ArrayList externalVariables = operator.getExternalVariables();
272 if (externalVariables != null) {
273 try {
274 for (int i = 0; i < externalVariables.size(); i++) {
275 Variable vari = (Variable) externalVariables.get(i);
276 Object strvalue = context.getVariableValue(vari);
277 if (strvalue == null)
278 throw new MediatorException("Could not find expression while replacing variable");
279 sb.append("declare variable $");
280 QName qname = vari.getVarName();
282 NamespaceContextStack contextSatck = operator.getPlan().getModule().getDeclarations();
283 if (contextSatck != null) {
284 String prefix = contextSatck.getPrefix(qname.getNameSpace());
285 if (prefix != null && prefix.length() != 0) {
286 sb.append(prefix);
287 sb.append(":");
288 }
289 }
290 sb.append(qname.getLocalName());
291 sb.append(" := {");
292 if (strvalue instanceof ArrayList ) {
293 sb.append("(");
294 ArrayList list = (ArrayList )strvalue;
295 for (int j=0;j<list.size();j++) {
296 if (j!=0)
297 sb.append(",");
298 strvalue = list.get(j);
299 if (strvalue instanceof String ) {
300 sb.append("\"");
301 sb.append(strvalue.toString());
302 sb.append("\"");
303 } else
304 sb.append(strvalue.toString());
305 }
306 sb.append(")");
307 } else {
308 if (strvalue instanceof String ) {
309 sb.append("\"");
310 sb.append(strvalue.toString());
311 sb.append("\"");
312 } else
313 sb.append(strvalue.toString());
314 }
315 sb.append("};\n");
316 }
317 } catch (XQueryException xqe) {
318 throw new MediatorException(xqe.getMessage(), xqe);
319 }
320 }
321 sb.append(expression.getStringValue(operator.getPlan().getModule().getDeclarations()));
323
324 if (log.isDebugEnabled())
325 log.debug("SOURCE EXECUTING \n" + sb.toString());
326
327 try {
328 resultset = statement.executeQuery(sb.toString());
329
330 if (!resultset.hasNext()) {
331 resultset.close();
332 resultset = null;
333 statement.close();
334 setFinishedWhenEmpty();
335 }
336 } catch (XMLDBCException xe) {
337 throw new MediatorException(xe.getMessage(), xe);
338 }
339 }
340
341 public SourceResultSet(OpSource operator, DynamicContext context, PreparedXMLStatement statement) throws MediatorException {
342 super(operator, context);
343
344 try {
345 ArrayList externalVariables = operator.getExternalVariables();
346 if (externalVariables != null) {
347 try {
348 for (int i = 0; i < externalVariables.size(); i++) {
349 Variable vari = (Variable) externalVariables.get(i);
350 Object strvalue = context.getVariableValue(vari);
351 if (strvalue == null)
352 throw new MediatorException("Could not find expression while replacing variable");
353 ((PreparedXMLStatement) statement).setObject(vari.getVarName().getNameSpace(), vari.getVarName().getName(), strvalue);
354 }
355 } catch (XQueryException xqe) {
356 throw new XMLDBCException(xqe.getMessage());
357 }
358 }
359 resultset = ((PreparedXMLStatement) statement).executeQuery();
360
361 if (!resultset.hasNext()) {
362 resultset.close();
363 resultset = null;
364 setFinishedWhenEmpty();
365 }
366 } catch (XMLDBCException xe) {
367 throw new MediatorException(xe.getMessage(), xe);
368 }
369 }
370
371
379 protected void evaluate(boolean non_blocking) throws MediatorException {
380
381 if (resultset == null)
382 return;
383
384
386 if (this.operator.isLet())
387 non_blocking = false;
388 try {
389 if (thandler == null) {
390 psvip = this.resultset.getPSVInfoSetProvider();
391 if (psvip == null) {
392 SchemaValidationContext svc = new SchemaValidationContext(this.operator.getPlan().getSchemaManager());
393 vsh = new ValidatingSchemaHandler(svc, false);
394 thandler = new SAX2DOM(svc);
395 vsh.setContentHandler(thandler);
396 vsh.setErrorHandler(new ErrorHandler () {
397 public void warning(SAXParseException ex) throws SAXException {
398 }
399
400 public void error(SAXParseException ex) throws SAXException {
401 System.err.println(ex);
402 }
403
404 public void fatalError(SAXParseException ex) throws SAXException {
405 }
406 });
407 resultset.setContentHandler(vsh);
408 } else {
409 thandler = new SAX2DOM(psvip);
410 resultset.setContentHandler(thandler);
411 }
412 }
413 while (true) {
414 Tuple tuple = new Tuple(this);
415 thandler.init(tuple);
416 if (resultset.hasNext()) {
417 if (vsh != null)
418 vsh.startDocument();
419 else
420 thandler.startDocument();
421 resultset.nextAsSAX();
422 if (vsh != null)
423 vsh.endDocument();
424 else
425 thandler.endDocument();
426 if (this.operator.isLet()) {
427 if (this.buftuples.size() == 0) {
428 tuple.fillIdentifiers();
429 buftuples.add(tuple);
430 } else {
431 Tuple first = (Tuple) this.buftuples.get(0);
432 first.appendTuple(tuple);
433 }
434 } else {
435 tuple.fillIdentifiers();
436 buftuples.add(tuple);
437 }
438 if (non_blocking && !buftuples.isEmpty()) {
440 if (resultset != null && !resultset.hasNext()) {
441 resultset.close();
442 resultset = null;
443 if (statement != null)
444 statement.close();
445 setFinishedWhenEmpty();
446 }
447 break;
448 }
449 } else {
450 resultset.close();
451 resultset = null;
452 if (statement != null)
453 statement.close();
454 setFinishedWhenEmpty();
455 return;
456 }
457 }
458 } catch (XMLDBCException xe) {
459 throw new MediatorException("AlgSource.evaluate: " + xe.getMessage(), xe);
460 } catch (SAXException saxe) {
461 throw new MediatorException("AlgSource.evaluate: " + saxe.getMessage(), saxe);
462 }
463 }
464
465 protected void finalize() {
466 try {
467 if (null != resultset) {
468 resultset.close();
469 if (statement != null)
470 statement.close();
471 }
472 } catch (Exception ex) {
473 }
474 ;
475 }
476 } |
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