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1
2 import com.saxonica.validate.SchemaAwareConfiguration;
3 import net.sf.saxon.event.Sink;
4 import net.sf.saxon.Configuration;
5 import net.sf.saxon.TransformerFactoryImpl;
6 import net.sf.saxon.tree.TreeBuilder;
7 import net.sf.saxon.event.PipelineConfiguration;
8 import net.sf.saxon.event.Receiver;
9 import net.sf.saxon.event.ResultWrapper;
10 import net.sf.saxon.event.Sink;
11 import net.sf.saxon.om.NodeInfo;
12 import net.sf.saxon.om.Validation;
13 import net.sf.saxon.pull.*;
14 import net.sf.saxon.query.DynamicQueryContext;
15 import net.sf.saxon.query.StaticQueryContext;
16 import net.sf.saxon.query.XQueryExpression;
17 import net.sf.saxon.tinytree.TinyBuilder;
18 import net.sf.saxon.trans.XPathException;
19 import net.sf.saxon.value.Value;
20
21 import javax.xml.transform.*;
22 import javax.xml.transform.stream.StreamResult  ;
23 import javax.xml.transform.stream.StreamSource ;
24 import java.io.*;
25 import java.util.Properties ;
26
27
35
36 public class PullExamples {
37
38 private Configuration config;
39
40
43
44 public void serialize(PullProvider in, OutputStream out) throws XPathException, IOException {
45 Properties props = new Properties ();
46 props.setProperty(OutputKeys.METHOD, "xml");
47 props.setProperty(OutputKeys.INDENT, "yes");
48 Receiver receiver = ResultWrapper.getReceiver(new StreamResult (out),
49 in.getPipelineConfiguration(),
50 props);
51 new PullPushCopier(in, receiver).copy();
52 }
53
54
58
59 public void validate(PullProvider in) throws XPathException, IOException {
60 SchemaAwareConfiguration config = new SchemaAwareConfiguration();
61 in.getPipelineConfiguration().setConfiguration(config);
62 Receiver sink = new Sink();
63 sink.setPipelineConfiguration(in.getPipelineConfiguration());
64 Receiver validator = config.getDocumentValidator(
65 sink, in.getSourceLocator().getSystemId(), config.getNamePool(), Validation.STRICT, null);
66 validator.setPipelineConfiguration(in.getPipelineConfiguration());
67 new PullPushCopier(in, validator).copy();
69 }
70
71
74
75 public void transform(PullProvider in, File stylesheet, OutputStream out) throws TransformerException {
76 TransformerFactory factory = new TransformerFactoryImpl();
77 Templates templates = factory.newTemplates(new StreamSource (stylesheet));
78 Transformer transformer = templates.newTransformer();
79 transformer.transform(
80 new PullSource(in),
81 new StreamResult (out)
82 );
83 }
84
85
88
89 public void query(PullProvider in, String query, OutputStream out) throws XPathException {
90 final StaticQueryContext sqc = new StaticQueryContext(config);
91 final XQueryExpression exp = sqc.compileQuery(query);
92 final DynamicQueryContext dynamicContext = new DynamicQueryContext(config);
93 dynamicContext.setContextNode(sqc.buildDocument(new PullSource(in)));
94 Properties props = new Properties ();
95 props.setProperty(OutputKeys.INDENT, "yes");
96 exp.run(dynamicContext, new StreamResult (out), props);
97 }
98
99
102
103 public NodeInfo build(PullProvider in) throws XPathException {
104 TinyBuilder builder = new TinyBuilder();
105 builder.setPipelineConfiguration(in.getPipelineConfiguration());
106 new PullPushCopier(in, builder).copy();
107 return builder.getCurrentRoot();
108 }
109
110
113
114 public NodeInfo buildStandardTree(PullProvider in) throws XPathException {
115 TreeBuilder builder = new TreeBuilder();
116 builder.setPipelineConfiguration(in.getPipelineConfiguration());
117 builder.open();
118 new PullPushCopier(in, builder).copy();
119 builder.close();
120 return builder.getCurrentRoot();
121 }
122
123
126
127 public PullProvider getParser(File input) throws FileNotFoundException, XPathException {
128 StaxBridge parser = new StaxBridge();
129 parser.setInputStream(input.toURI().toString(), new FileInputStream(input));
130 parser.setPipelineConfiguration(config.makePipelineConfiguration());
131 return parser;
132 }
133
134
137
138 public PullProvider getTreeWalker(NodeInfo root) {
139 return TreeWalker.makeTreeWalker(root);
140 }
141
142
146
147 public PullProvider pullQueryResults(NodeInfo source, String query) throws XPathException {
148 final StaticQueryContext sqc = new StaticQueryContext(config);
149 final XQueryExpression exp = sqc.compileQuery(query);
150 final DynamicQueryContext dynamicContext = new DynamicQueryContext(config);
151 dynamicContext.setContextNode(source);
152 PullProvider pull = new PullFromIterator(exp.iterator(dynamicContext));
153 pull = new PullNamespaceReducer(pull);
154 pull.setPipelineConfiguration(config.makePipelineConfiguration());
155 return pull;
156 }
157
158
162
163 public void removePriceElements(PullProvider in, OutputStream out) throws IOException, XPathException {
164 final int priceElement = config.getNamePool().allocate("", "", "PRICE");
165 PullFilter filter = new PullFilter(in) {
166 public int next() throws XPathException {
167 currentEvent = super.next();
168 if (currentEvent == START_ELEMENT && getFingerprint() == priceElement) {
169 super.skipToMatchingEnd();
170 currentEvent = next();
171 }
172 return currentEvent;
173 }
174 };
175 serialize(filter, out);
176 }
177
178
182
183 public void displayAveragePrice(PullProvider in, OutputStream out) throws IOException, XPathException {
184 final int priceElement = config.getNamePool().allocate("", "", "PRICE");
185 double total = 0;
186 int count = 0;
187 while (true) {
188 int event = in.next();
189 if (event == PullProvider.END_OF_INPUT) {
190 break;
191 }
192 if (event == PullProvider.START_ELEMENT && in.getFingerprint() == priceElement) {
193 double value = Value.stringToNumber(in.getStringValue());
194 total += value;
195 count++;
196 }
197 }
198 double average = (count==0 ? Double.NaN : total/count);
199 String result = "<result>" + average + "</result>";
200 OutputStreamWriter writer = new OutputStreamWriter(out);
201 writer.write(result);
202 writer.flush();
203 }
204
205
215
216 public static void main(String [] args) throws Exception {
217 String examples;
218 if (args.length < 1 || args[0].equals("#")) {
219 examples = "abcdefghijklmnopqrstuvwxyz";
220 } else {
221 examples = args[0];
222 }
223 File input = null;
224 OutputStream output = null;
225 String query = null;
226 File stylesheet = null;
227
228 for (int i=1; i<args.length; i++) {
229 if (args[i].equals("-s")) {
230 input = new File(args[++i]);
231 } else if (args[i].equals("-o")) {
232 output = new FileOutputStream(new File(args[++i]));
233 } else if (args[i].equals("-q")) {
234 query = readFile(new File(args[++i]));
235 } else if (args[i].equals("-xsl")) {
236 stylesheet = new File(args[++i]);
237 } else {
238 System.err.println("Unknown argument " + args[i]);
239 }
240 }
241
242 if (input==null) {
243 input = new File("../data/books.xml");
244 }
245
246 if (output==null) {
247 output = System.out;
248 }
249
250 PullExamples o = new PullExamples();
251 Configuration config = new Configuration();
252 config.setLazyConstructionMode(true);
253 o.config = config;
254
255 PipelineConfiguration pipe = config.makePipelineConfiguration();
256 for (int i=0; i<examples.length(); i++) {
257 char ex = examples.charAt(i);
258 switch (ex) {
259 case 'a': {
260 System.out.println("\n\n=== Serialize the input to the output ===\n");
261
262 PullProvider p = o.getParser(input);
263 p.setPipelineConfiguration(pipe);
264 o.serialize(p, output);
265 break;
266 }
267 case 'b': {
268 System.out.println("\n\n=== Validate the input ===\n");
269
270 PullProvider p = o.getParser(input);
271 p.setPipelineConfiguration(pipe);
272 o.validate(p);
273 break;
274 }
275 case 'c': {
276 System.out.println("\n\n=== Transform the input to the output ===\n");
277
278 if (stylesheet == null) {
279 System.err.println("** No stylesheet supplied");
280 break;
281 }
282 PullProvider p = o.getParser(input);
283 p.setPipelineConfiguration(pipe);
284 o.transform(p, stylesheet, output);
285 break;
286 }
287 case 'd': {
288 System.out.println("\n\n=== Run XQuery against the input ===\n");
289 if (query == null) {
290 query = "<result>{.}</result>";
291 }
292 PullProvider p = o.getParser(input);
293 p.setPipelineConfiguration(pipe);
294 o.query(p, query, output);
295 break;
296 }
297 case 'e': {
298 System.out.println("\n\n=== Remove PRICE elements from the input ===\n");
299
300 PullProvider p = o.getParser(input);
301 p.setPipelineConfiguration(pipe);
302 o.removePriceElements(p, output);
303 break;
304 }
305 case 'f': {
306 System.out.println("\n\n=== Compute average of PRICE elements in the input ===\n");
307
308 PullProvider p = o.getParser(input);
309 p.setPipelineConfiguration(pipe);
310 o.displayAveragePrice(p, output);
311 break;
312 }
313 case 'g': {
314 System.out.println("\n\n=== Obtain query results using a pull iterator ===\n");
315
316 NodeInfo node = new StaticQueryContext(config)
317 .buildDocument(new StreamSource (input));
318 PullProvider p = o.pullQueryResults(node,
319
320 "declare function local:f() {"+
321 "for $var1 in (<abc/>, <def/>)"+
322 "return <e xmlns:x='x1'><f xmlns:y='y1' xmlns:x='x2'>xyz</f></e>};"+
323 "local:f()"
324
325 );
326 o.serialize(new PullTracer(p), output);
327 break;
328 }
329 case 'h': {
330 System.out.println("\n\n=== Obtain query results using a pull iterator on a 'standard' tree ===\n");
331
332 PullProvider p1 = o.getParser(input);
333 p1.setPipelineConfiguration(pipe);
334 NodeInfo node = o.buildStandardTree(p1);
335 PullProvider p2 = o.pullQueryResults(node,
336 "//CATEGORIES"
337 );
338 o.serialize(p2, output);
339 }
340 }
341 }
342 }
343
344
347
348 public static String readFile(File file) throws IOException {
349 Reader reader = new FileReader(file);
350 char[] buffer = new char[4096];
351 StringBuffer sb = new StringBuffer (4096);
352 while (true) {
353 int n = reader.read(buffer);
354 if (n>0) {
355 sb.append(buffer, 0, n);
356 } else {
357 break;
358 }
359 }
360 return sb.toString();
361 }
362
363
364
365 }
366
367 |
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