1 /*
2 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.sql;
27
28 import java.io.InputStream;
29 import java.io.OutputStream;
30 import java.io.Reader;
31 import java.io.Writer;
32
33 import javax.xml.transform.Result;
34 import javax.xml.transform.Source;
35
36 /**
37 * The mapping in the JavaTM programming language for the SQL XML type.
38 * XML is a built-in type that stores an XML value
39 * as a column value in a row of a database table.
40 * By default drivers implement an SQLXML object as
41 * a logical pointer to the XML data
42 * rather than the data itself.
43 * An SQLXML object is valid for the duration of the transaction in which it was created.
44 * <p>
45 * The SQLXML interface provides methods for accessing the XML value
46 * as a String, a Reader or Writer, or as a Stream. The XML value
47 * may also be accessed through a Source or set as a Result, which
48 * are used with XML Parser APIs such as DOM, SAX, and StAX, as
49 * well as with XSLT transforms and XPath evaluations.
50 * <p>
51 * Methods in the interfaces ResultSet, CallableStatement, and PreparedStatement,
52 * such as getSQLXML allow a programmer to access an XML value.
53 * In addition, this interface has methods for updating an XML value.
54 * <p>
55 * The XML value of the SQLXML instance may be obtained as a BinaryStream using
56 * <pre>
57 * SQLXML sqlxml = resultSet.getSQLXML(column);
58 * InputStream binaryStream = sqlxml.getBinaryStream();
59 * </pre>
60 * For example, to parse an XML value with a DOM parser:
61 * <pre>
62 * DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
63 * Document result = parser.parse(binaryStream);
64 * </pre>
65 * or to parse an XML value with a SAX parser to your handler:
66 * <pre>
67 * SAXParser parser = SAXParserFactory.newInstance().newSAXParser();
68 * parser.parse(binaryStream, myHandler);
69 * </pre>
70 * or to parse an XML value with a StAX parser:
71 * <pre>
72 * XMLInputFactory factory = XMLInputFactory.newInstance();
73 * XMLStreamReader streamReader = factory.createXMLStreamReader(binaryStream);
74 * </pre>
75 * <p>
76 * Because databases may use an optimized representation for the XML,
77 * accessing the value through getSource() and
78 * setResult() can lead to improved processing performance
79 * without serializing to a stream representation and parsing the XML.
80 * <p>
81 * For example, to obtain a DOM Document Node:
82 * <pre>
83 * DOMSource domSource = sqlxml.getSource(DOMSource.class);
84 * Document document = (Document) domSource.getNode();
85 * </pre>
86 * or to set the value to a DOM Document Node to myNode:
87 * <pre>
88 * DOMResult domResult = sqlxml.setResult(DOMResult.class);
89 * domResult.setNode(myNode);
90 * </pre>
91 * or, to send SAX events to your handler:
92 * <pre>
93 * SAXSource saxSource = sqlxml.getSource(SAXSource.class);
94 * XMLReader xmlReader = saxSource.getXMLReader();
95 * xmlReader.setContentHandler(myHandler);
96 * xmlReader.parse(saxSource.getInputSource());
97 * </pre>
98 * or, to set the result value from SAX events:
99 * <pre>
100 * SAXResult saxResult = sqlxml.setResult(SAXResult.class);
101 * ContentHandler contentHandler = saxResult.getXMLReader().getContentHandler();
102 * contentHandler.startDocument();
103 * // set the XML elements and attributes into the result
104 * contentHandler.endDocument();
105 * </pre>
106 * or, to obtain StAX events:
107 * <pre>
108 * StAXSource staxSource = sqlxml.getSource(StAXSource.class);
109 * XMLStreamReader streamReader = staxSource.getXMLStreamReader();
110 * </pre>
111 * or, to set the result value from StAX events:
112 * <pre>
113 * StAXResult staxResult = sqlxml.setResult(StAXResult.class);
114 * XMLStreamWriter streamWriter = staxResult.getXMLStreamWriter();
115 * </pre>
116 * or, to perform XSLT transformations on the XML value using the XSLT in xsltFile
117 * output to file resultFile:
118 * <pre>
119 * File xsltFile = new File("a.xslt");
120 * File myFile = new File("result.xml");
121 * Transformer xslt = TransformerFactory.newInstance().newTransformer(new StreamSource(xsltFile));
122 * Source source = sqlxml.getSource(null);
123 * Result result = new StreamResult(myFile);
124 * xslt.transform(source, result);
125 * </pre>
126 * or, to evaluate an XPath expression on the XML value:
127 * <pre>
128 * XPath xpath = XPathFactory.newInstance().newXPath();
129 * DOMSource domSource = sqlxml.getSource(DOMSource.class);
130 * Document document = (Document) domSource.getNode();
131 * String expression = "/foo/@bar";
132 * String barValue = xpath.evaluate(expression, document);
133 * </pre>
134 * To set the XML value to be the result of an XSLT transform:
135 * <pre>
136 * File sourceFile = new File("source.xml");
137 * Transformer xslt = TransformerFactory.newInstance().newTransformer(new StreamSource(xsltFile));
138 * Source streamSource = new StreamSource(sourceFile);
139 * Result result = sqlxml.setResult(null);
140 * xslt.transform(streamSource, result);
141 * </pre>
142 * Any Source can be transformed to a Result using the identity transform
143 * specified by calling newTransformer():
144 * <pre>
145 * Transformer identity = TransformerFactory.newInstance().newTransformer();
146 * Source source = sqlxml.getSource(null);
147 * File myFile = new File("result.xml");
148 * Result result = new StreamResult(myFile);
149 * identity.transform(source, result);
150 * </pre>
151 * To write the contents of a Source to standard output:
152 * <pre>
153 * Transformer identity = TransformerFactory.newInstance().newTransformer();
154 * Source source = sqlxml.getSource(null);
155 * Result result = new StreamResult(System.out);
156 * identity.transform(source, result);
157 * </pre>
158 * To create a DOMSource from a DOMResult:
159 * <pre>
160 * DOMSource domSource = new DOMSource(domResult.getNode());
161 * </pre>
162 * <p>
163 * Incomplete or invalid XML values may cause an SQLException when
164 * set or the exception may occur when execute() occurs. All streams
165 * must be closed before execute() occurs or an SQLException will be thrown.
166 * <p>
167 * Reading and writing XML values to or from an SQLXML object can happen at most once.
168 * The conceptual states of readable and not readable determine if one
169 * of the reading APIs will return a value or throw an exception.
170 * The conceptual states of writable and not writable determine if one
171 * of the writing APIs will set a value or throw an exception.
172 * <p>
173 * The state moves from readable to not readable once free() or any of the
174 * reading APIs are called: getBinaryStream(), getCharacterStream(), getSource(), and getString().
175 * Implementations may also change the state to not writable when this occurs.
176 * <p>
177 * The state moves from writable to not writeable once free() or any of the
178 * writing APIs are called: setBinaryStream(), setCharacterStream(), setResult(), and setString().
179 * Implementations may also change the state to not readable when this occurs.
180 * <p>
181 * <p>
182 * All methods on the <code>SQLXML</code> interface must be fully implemented if the
183 * JDBC driver supports the data type.
184 *
185 * @see javax.xml.parsers
186 * @see javax.xml.stream
187 * @see javax.xml.transform
188 * @see javax.xml.xpath
189 * @since 1.6
190 */
191 public interface SQLXML
192 {
193 /**
194 * This method closes this object and releases the resources that it held.
195 * The SQL XML object becomes invalid and neither readable or writeable
196 * when this method is called.
197 *
198 * After <code>free</code> has been called, any attempt to invoke a
199 * method other than <code>free</code> will result in a <code>SQLException</code>
200 * being thrown. If <code>free</code> is called multiple times, the subsequent
201 * calls to <code>free</code> are treated as a no-op.
202 * @throws SQLException if there is an error freeing the XML value.
203 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
204 * this method
205 * @since 1.6
206 */
207 void free() throws SQLException;
208
209 /**
210 * Retrieves the XML value designated by this SQLXML instance as a stream.
211 * The bytes of the input stream are interpreted according to appendix F of the XML 1.0 specification.
212 * The behavior of this method is the same as ResultSet.getBinaryStream()
213 * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.
214 * <p>
215 * The SQL XML object becomes not readable when this method is called and
216 * may also become not writable depending on implementation.
217 *
218 * @return a stream containing the XML data.
219 * @throws SQLException if there is an error processing the XML value.
220 * An exception is thrown if the state is not readable.
221 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
222 * this method
223 * @since 1.6
224 */
225 InputStream getBinaryStream() throws SQLException;
226
227 /**
228 * Retrieves a stream that can be used to write the XML value that this SQLXML instance represents.
229 * The stream begins at position 0.
230 * The bytes of the stream are interpreted according to appendix F of the XML 1.0 specification
231 * The behavior of this method is the same as ResultSet.updateBinaryStream()
232 * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.
233 * <p>
234 * The SQL XML object becomes not writeable when this method is called and
235 * may also become not readable depending on implementation.
236 *
237 * @return a stream to which data can be written.
238 * @throws SQLException if there is an error processing the XML value.
239 * An exception is thrown if the state is not writable.
240 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
241 * this method
242 * @since 1.6
243 */
244 OutputStream setBinaryStream() throws SQLException;
245
246 /**
247 * Retrieves the XML value designated by this SQLXML instance as a java.io.Reader object.
248 * The format of this stream is defined by org.xml.sax.InputSource,
249 * where the characters in the stream represent the unicode code points for
250 * XML according to section 2 and appendix B of the XML 1.0 specification.
251 * Although an encoding declaration other than unicode may be present,
252 * the encoding of the stream is unicode.
253 * The behavior of this method is the same as ResultSet.getCharacterStream()
254 * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.
255 * <p>
256 * The SQL XML object becomes not readable when this method is called and
257 * may also become not writable depending on implementation.
258 *
259 * @return a stream containing the XML data.
260 * @throws SQLException if there is an error processing the XML value.
261 * The getCause() method of the exception may provide a more detailed exception, for example,
262 * if the stream does not contain valid characters.
263 * An exception is thrown if the state is not readable.
264 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
265 * this method
266 * @since 1.6
267 */
268 Reader getCharacterStream() throws SQLException;
269
270 /**
271 * Retrieves a stream to be used to write the XML value that this SQLXML instance represents.
272 * The format of this stream is defined by org.xml.sax.InputSource,
273 * where the characters in the stream represent the unicode code points for
274 * XML according to section 2 and appendix B of the XML 1.0 specification.
275 * Although an encoding declaration other than unicode may be present,
276 * the encoding of the stream is unicode.
277 * The behavior of this method is the same as ResultSet.updateCharacterStream()
278 * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.
279 * <p>
280 * The SQL XML object becomes not writeable when this method is called and
281 * may also become not readable depending on implementation.
282 *
283 * @return a stream to which data can be written.
284 * @throws SQLException if there is an error processing the XML value.
285 * The getCause() method of the exception may provide a more detailed exception, for example,
286 * if the stream does not contain valid characters.
287 * An exception is thrown if the state is not writable.
288 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
289 * this method
290 * @since 1.6
291 */
292 Writer setCharacterStream() throws SQLException;
293
294 /**
295 * Returns a string representation of the XML value designated by this SQLXML instance.
296 * The format of this String is defined by org.xml.sax.InputSource,
297 * where the characters in the stream represent the unicode code points for
298 * XML according to section 2 and appendix B of the XML 1.0 specification.
299 * Although an encoding declaration other than unicode may be present,
300 * the encoding of the String is unicode.
301 * The behavior of this method is the same as ResultSet.getString()
302 * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.
303 * <p>
304 * The SQL XML object becomes not readable when this method is called and
305 * may also become not writable depending on implementation.
306 *
307 * @return a string representation of the XML value designated by this SQLXML instance.
308 * @throws SQLException if there is an error processing the XML value.
309 * The getCause() method of the exception may provide a more detailed exception, for example,
310 * if the stream does not contain valid characters.
311 * An exception is thrown if the state is not readable.
312 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
313 * this method
314 * @since 1.6
315 */
316 String getString() throws SQLException;
317
318 /**
319 * Sets the XML value designated by this SQLXML instance to the given String representation.
320 * The format of this String is defined by org.xml.sax.InputSource,
321 * where the characters in the stream represent the unicode code points for
322 * XML according to section 2 and appendix B of the XML 1.0 specification.
323 * Although an encoding declaration other than unicode may be present,
324 * the encoding of the String is unicode.
325 * The behavior of this method is the same as ResultSet.updateString()
326 * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.
327 * <p>
328 * The SQL XML object becomes not writeable when this method is called and
329 * may also become not readable depending on implementation.
330 *
331 * @param value the XML value
332 * @throws SQLException if there is an error processing the XML value.
333 * The getCause() method of the exception may provide a more detailed exception, for example,
334 * if the stream does not contain valid characters.
335 * An exception is thrown if the state is not writable.
336 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
337 * this method
338 * @since 1.6
339 */
340 void setString(String value) throws SQLException;
341
342 /**
343 * Returns a Source for reading the XML value designated by this SQLXML instance.
344 * Sources are used as inputs to XML parsers and XSLT transformers.
345 * <p>
346 * Sources for XML parsers will have namespace processing on by default.
347 * The systemID of the Source is implementation dependent.
348 * <p>
349 * The SQL XML object becomes not readable when this method is called and
350 * may also become not writable depending on implementation.
351 * <p>
352 * Note that SAX is a callback architecture, so a returned
353 * SAXSource should then be set with a content handler that will
354 * receive the SAX events from parsing. The content handler
355 * will receive callbacks based on the contents of the XML.
356 * <pre>
357 * SAXSource saxSource = sqlxml.getSource(SAXSource.class);
358 * XMLReader xmlReader = saxSource.getXMLReader();
359 * xmlReader.setContentHandler(myHandler);
360 * xmlReader.parse(saxSource.getInputSource());
361 * </pre>
362 *
363 * @param sourceClass The class of the source, or null.
364 * If the class is null, a vendor specifc Source implementation will be returned.
365 * The following classes are supported at a minimum:
366 * <pre>
367 * javax.xml.transform.dom.DOMSource - returns a DOMSource
368 * javax.xml.transform.sax.SAXSource - returns a SAXSource
369 * javax.xml.transform.stax.StAXSource - returns a StAXSource
370 * javax.xml.transform.stream.StreamSource - returns a StreamSource
371 * </pre>
372 * @return a Source for reading the XML value.
373 * @throws SQLException if there is an error processing the XML value
374 * or if this feature is not supported.
375 * The getCause() method of the exception may provide a more detailed exception, for example,
376 * if an XML parser exception occurs.
377 * An exception is thrown if the state is not readable.
378 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
379 * this method
380 * @since 1.6
381 */
382 <T extends Source> T getSource(Class<T> sourceClass) throws SQLException;
383
384 /**
385 * Returns a Result for setting the XML value designated by this SQLXML instance.
386 * <p>
387 * The systemID of the Result is implementation dependent.
388 * <p>
389 * The SQL XML object becomes not writeable when this method is called and
390 * may also become not readable depending on implementation.
391 * <p>
392 * Note that SAX is a callback architecture and the returned
393 * SAXResult has a content handler assigned that will receive the
394 * SAX events based on the contents of the XML. Call the content
395 * handler with the contents of the XML document to assign the values.
396 * <pre>
397 * SAXResult saxResult = sqlxml.setResult(SAXResult.class);
398 * ContentHandler contentHandler = saxResult.getXMLReader().getContentHandler();
399 * contentHandler.startDocument();
400 * // set the XML elements and attributes into the result
401 * contentHandler.endDocument();
402 * </pre>
403 *
404 * @param resultClass The class of the result, or null.
405 * If resultClass is null, a vendor specific Result implementation will be returned.
406 * The following classes are supported at a minimum:
407 * <pre>
408 * javax.xml.transform.dom.DOMResult - returns a DOMResult
409 * javax.xml.transform.sax.SAXResult - returns a SAXResult
410 * javax.xml.transform.stax.StAXResult - returns a StAXResult
411 * javax.xml.transform.stream.StreamResult - returns a StreamResult
412 * </pre>
413 * @return Returns a Result for setting the XML value.
414 * @throws SQLException if there is an error processing the XML value
415 * or if this feature is not supported.
416 * The getCause() method of the exception may provide a more detailed exception, for example,
417 * if an XML parser exception occurs.
418 * An exception is thrown if the state is not writable.
419 * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
420 * this method
421 * @since 1.6
422 */
423 <T extends Result> T setResult(Class<T> resultClass) throws SQLException;
424
425 }