/* * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.sql; import java.io.InputStream;import java.io.OutputStream;import java.io.Reader;import java.io.Writer; import javax.xml.transform.Result;import javax.xml.transform.Source; /** * The mapping in the JavaTM programming language for the SQL XML type. * XML is a built-in type that stores an XML value * as a column value in a row of a database table. * By default drivers implement an SQLXML object as * a logical pointer to the XML data * rather than the data itself. * An SQLXML object is valid for the duration of the transaction in which it was created. * <p> * The SQLXML interface provides methods for accessing the XML value * as a String, a Reader or Writer, or as a Stream.  The XML value * may also be accessed through a Source or set as a Result, which * are used with XML Parser APIs such as DOM, SAX, and StAX, as * well as with XSLT transforms and XPath evaluations. * <p> * Methods in the interfaces ResultSet, CallableStatement, and PreparedStatement, * such as getSQLXML allow a programmer to access an XML value. * In addition, this interface has methods for updating an XML value. * <p> * The XML value of the SQLXML instance may be obtained as a BinaryStream using * <pre> *   SQLXML sqlxml = resultSet.getSQLXML(column); *   InputStream binaryStream = sqlxml.getBinaryStream(); * </pre> * For example, to parse an XML value with a DOM parser: * <pre> *   DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder(); *   Document result = parser.parse(binaryStream); * </pre> * or to parse an XML value with a SAX parser to your handler: * <pre> *   SAXParser parser = SAXParserFactory.newInstance().newSAXParser(); *   parser.parse(binaryStream, myHandler); * </pre> * or to parse an XML value with a StAX parser: * <pre> *   XMLInputFactory factory = XMLInputFactory.newInstance(); *   XMLStreamReader streamReader = factory.createXMLStreamReader(binaryStream); * </pre> * <p> * Because databases may use an optimized representation for the XML, * accessing the value through getSource() and * setResult() can lead to improved processing performance * without serializing to a stream representation and parsing the XML. * <p> * For example, to obtain a DOM Document Node: * <pre> *   DOMSource domSource = sqlxml.getSource(DOMSource.class); *   Document document = (Document) domSource.getNode(); * </pre> * or to set the value to a DOM Document Node to myNode: * <pre> *   DOMResult domResult = sqlxml.setResult(DOMResult.class); *   domResult.setNode(myNode); * </pre> * or, to send SAX events to your handler: * <pre> *   SAXSource saxSource = sqlxml.getSource(SAXSource.class); *   XMLReader xmlReader = saxSource.getXMLReader(); *   xmlReader.setContentHandler(myHandler); *   xmlReader.parse(saxSource.getInputSource()); * </pre> * or, to set the result value from SAX events: * <pre> *   SAXResult saxResult = sqlxml.setResult(SAXResult.class); *   ContentHandler contentHandler = saxResult.getXMLReader().getContentHandler(); *   contentHandler.startDocument(); *   // set the XML elements and attributes into the result *   contentHandler.endDocument(); * </pre> * or, to obtain StAX events: * <pre> *   StAXSource staxSource = sqlxml.getSource(StAXSource.class); *   XMLStreamReader streamReader = staxSource.getXMLStreamReader(); * </pre> * or, to set the result value from StAX events: * <pre> *   StAXResult staxResult = sqlxml.setResult(StAXResult.class); *   XMLStreamWriter streamWriter = staxResult.getXMLStreamWriter(); * </pre> * or, to perform XSLT transformations on the XML value using the XSLT in xsltFile * output to file resultFile: * <pre> *   File xsltFile = new File("a.xslt"); *   File myFile = new File("result.xml"); *   Transformer xslt = TransformerFactory.newInstance().newTransformer(new StreamSource(xsltFile)); *   Source source = sqlxml.getSource(null); *   Result result = new StreamResult(myFile); *   xslt.transform(source, result); * </pre> * or, to evaluate an XPath expression on the XML value: * <pre> *   XPath xpath = XPathFactory.newInstance().newXPath(); *   DOMSource domSource = sqlxml.getSource(DOMSource.class); *   Document document = (Document) domSource.getNode(); *   String expression = "/foo/@bar"; *   String barValue = xpath.evaluate(expression, document); * </pre> * To set the XML value to be the result of an XSLT transform: * <pre> *   File sourceFile = new File("source.xml"); *   Transformer xslt = TransformerFactory.newInstance().newTransformer(new StreamSource(xsltFile)); *   Source streamSource = new StreamSource(sourceFile); *   Result result = sqlxml.setResult(null); *   xslt.transform(streamSource, result); * </pre> * Any Source can be transformed to a Result using the identity transform * specified by calling newTransformer(): * <pre> *   Transformer identity = TransformerFactory.newInstance().newTransformer(); *   Source source = sqlxml.getSource(null); *   File myFile = new File("result.xml"); *   Result result = new StreamResult(myFile); *   identity.transform(source, result); * </pre> * To write the contents of a Source to standard output: * <pre> *   Transformer identity = TransformerFactory.newInstance().newTransformer(); *   Source source = sqlxml.getSource(null); *   Result result = new StreamResult(System.out); *   identity.transform(source, result); * </pre> * To create a DOMSource from a DOMResult: * <pre> *    DOMSource domSource = new DOMSource(domResult.getNode()); * </pre> * <p> * Incomplete or invalid XML values may cause an SQLException when * set or the exception may occur when execute() occurs.  All streams * must be closed before execute() occurs or an SQLException will be thrown. * <p> * Reading and writing XML values to or from an SQLXML object can happen at most once. * The conceptual states of readable and not readable determine if one * of the reading APIs will return a value or throw an exception. * The conceptual states of writable and not writable determine if one * of the writing APIs will set a value or throw an exception. * <p> * The state moves from readable to not readable once free() or any of the * reading APIs are called: getBinaryStream(), getCharacterStream(), getSource(), and getString(). * Implementations may also change the state to not writable when this occurs. * <p> * The state moves from writable to not writeable once free() or any of the * writing APIs are called: setBinaryStream(), setCharacterStream(), setResult(), and setString(). * Implementations may also change the state to not readable when this occurs. * <p>  * <p> * All methods on the <code>SQLXML</code> interface must be fully implemented if the * JDBC driver supports the data type. * * @see javax.xml.parsers * @see javax.xml.stream * @see javax.xml.transform * @see javax.xml.xpath * @since 1.6 */public interface SQLXML{  /**   * This method closes this object and releases the resources that it held.   * The SQL XML object becomes invalid and neither readable or writeable   * when this method is called.   *   * After <code>free</code> has been called, any attempt to invoke a   * method other than <code>free</code> will result in a <code>SQLException</code>   * being thrown.  If <code>free</code> is called multiple times, the subsequent   * calls to <code>free</code> are treated as a no-op.   * @throws SQLException if there is an error freeing the XML value.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  void free() throws SQLException;   /**   * Retrieves the XML value designated by this SQLXML instance as a stream.   * The bytes of the input stream are interpreted according to appendix F of the XML 1.0 specification.   * The behavior of this method is the same as ResultSet.getBinaryStream()   * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.   * <p>   * The SQL XML object becomes not readable when this method is called and   * may also become not writable depending on implementation.   *   * @return a stream containing the XML data.   * @throws SQLException if there is an error processing the XML value.   *   An exception is thrown if the state is not readable.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  InputStream getBinaryStream() throws SQLException;   /**   * Retrieves a stream that can be used to write the XML value that this SQLXML instance represents.   * The stream begins at position 0.   * The bytes of the stream are interpreted according to appendix F of the XML 1.0 specification   * The behavior of this method is the same as ResultSet.updateBinaryStream()   * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.   * <p>   * The SQL XML object becomes not writeable when this method is called and   * may also become not readable depending on implementation.   *   * @return a stream to which data can be written.   * @throws SQLException if there is an error processing the XML value.   *   An exception is thrown if the state is not writable.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  OutputStream setBinaryStream() throws SQLException;   /**   * Retrieves the XML value designated by this SQLXML instance as a java.io.Reader object.   * The format of this stream is defined by org.xml.sax.InputSource,   * where the characters in the stream represent the unicode code points for   * XML according to section 2 and appendix B of the XML 1.0 specification.   * Although an encoding declaration other than unicode may be present,   * the encoding of the stream is unicode.   * The behavior of this method is the same as ResultSet.getCharacterStream()   * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.   * <p>   * The SQL XML object becomes not readable when this method is called and   * may also become not writable depending on implementation.   *   * @return a stream containing the XML data.   * @throws SQLException if there is an error processing the XML value.   *   The getCause() method of the exception may provide a more detailed exception, for example,   *   if the stream does not contain valid characters.   *   An exception is thrown if the state is not readable.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  Reader getCharacterStream() throws SQLException;   /**   * Retrieves a stream to be used to write the XML value that this SQLXML instance represents.   * The format of this stream is defined by org.xml.sax.InputSource,   * where the characters in the stream represent the unicode code points for   * XML according to section 2 and appendix B of the XML 1.0 specification.   * Although an encoding declaration other than unicode may be present,   * the encoding of the stream is unicode.   * The behavior of this method is the same as ResultSet.updateCharacterStream()   * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.   * <p>   * The SQL XML object becomes not writeable when this method is called and   * may also become not readable depending on implementation.   *   * @return a stream to which data can be written.   * @throws SQLException if there is an error processing the XML value.   *   The getCause() method of the exception may provide a more detailed exception, for example,   *   if the stream does not contain valid characters.   *   An exception is thrown if the state is not writable.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  Writer setCharacterStream() throws SQLException;   /**   * Returns a string representation of the XML value designated by this SQLXML instance.   * The format of this String is defined by org.xml.sax.InputSource,   * where the characters in the stream represent the unicode code points for   * XML according to section 2 and appendix B of the XML 1.0 specification.   * Although an encoding declaration other than unicode may be present,   * the encoding of the String is unicode.   * The behavior of this method is the same as ResultSet.getString()   * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.   * <p>   * The SQL XML object becomes not readable when this method is called and   * may also become not writable depending on implementation.   *   * @return a string representation of the XML value designated by this SQLXML instance.   * @throws SQLException if there is an error processing the XML value.   *   The getCause() method of the exception may provide a more detailed exception, for example,   *   if the stream does not contain valid characters.   *   An exception is thrown if the state is not readable.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  String getString() throws SQLException;   /**   * Sets the XML value designated by this SQLXML instance to the given String representation.   * The format of this String is defined by org.xml.sax.InputSource,   * where the characters in the stream represent the unicode code points for   * XML according to section 2 and appendix B of the XML 1.0 specification.   * Although an encoding declaration other than unicode may be present,   * the encoding of the String is unicode.   * The behavior of this method is the same as ResultSet.updateString()   * when the designated column of the ResultSet has a type java.sql.Types of SQLXML.   * <p>   * The SQL XML object becomes not writeable when this method is called and   * may also become not readable depending on implementation.   *   * @param value the XML value   * @throws SQLException if there is an error processing the XML value.   *   The getCause() method of the exception may provide a more detailed exception, for example,   *   if the stream does not contain valid characters.   *   An exception is thrown if the state is not writable.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  void setString(String value) throws SQLException;   /**   * Returns a Source for reading the XML value designated by this SQLXML instance.   * Sources are used as inputs to XML parsers and XSLT transformers.   * <p>   * Sources for XML parsers will have namespace processing on by default.   * The systemID of the Source is implementation dependent.   * <p>   * The SQL XML object becomes not readable when this method is called and   * may also become not writable depending on implementation.   * <p>   * Note that SAX is a callback architecture, so a returned   * SAXSource should then be set with a content handler that will   * receive the SAX events from parsing.  The content handler   * will receive callbacks based on the contents of the XML.   * <pre>   *   SAXSource saxSource = sqlxml.getSource(SAXSource.class);   *   XMLReader xmlReader = saxSource.getXMLReader();   *   xmlReader.setContentHandler(myHandler);   *   xmlReader.parse(saxSource.getInputSource());   * </pre>   *   * @param sourceClass The class of the source, or null.   * If the class is null, a vendor specifc Source implementation will be returned.   * The following classes are supported at a minimum:   * <pre>   *   javax.xml.transform.dom.DOMSource - returns a DOMSource   *   javax.xml.transform.sax.SAXSource - returns a SAXSource   *   javax.xml.transform.stax.StAXSource - returns a StAXSource   *   javax.xml.transform.stream.StreamSource - returns a StreamSource   * </pre>   * @return a Source for reading the XML value.   * @throws SQLException if there is an error processing the XML value   *   or if this feature is not supported.   *   The getCause() method of the exception may provide a more detailed exception, for example,   *   if an XML parser exception occurs.   *   An exception is thrown if the state is not readable.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  <T extends Source> T getSource(Class<T> sourceClass) throws SQLException;   /**   * Returns a Result for setting the XML value designated by this SQLXML instance.   * <p>   * The systemID of the Result is implementation dependent.   * <p>   * The SQL XML object becomes not writeable when this method is called and   * may also become not readable depending on implementation.   * <p>   * Note that SAX is a callback architecture and the returned   * SAXResult has a content handler assigned that will receive the   * SAX events based on the contents of the XML.  Call the content   * handler with the contents of the XML document to assign the values.   * <pre>   *   SAXResult saxResult = sqlxml.setResult(SAXResult.class);   *   ContentHandler contentHandler = saxResult.getXMLReader().getContentHandler();   *   contentHandler.startDocument();   *   // set the XML elements and attributes into the result   *   contentHandler.endDocument();   * </pre>   *   * @param resultClass The class of the result, or null.   * If resultClass is null, a vendor specific Result implementation will be returned.   * The following classes are supported at a minimum:   * <pre>   *   javax.xml.transform.dom.DOMResult - returns a DOMResult   *   javax.xml.transform.sax.SAXResult - returns a SAXResult   *   javax.xml.transform.stax.StAXResult - returns a StAXResult   *   javax.xml.transform.stream.StreamResult - returns a StreamResult   * </pre>   * @return Returns a Result for setting the XML value.   * @throws SQLException if there is an error processing the XML value   *   or if this feature is not supported.   *   The getCause() method of the exception may provide a more detailed exception, for example,   *   if an XML parser exception occurs.   *   An exception is thrown if the state is not writable.   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support   * this method   * @since 1.6   */  <T extends Result> T setResult(Class<T> resultClass) throws SQLException; }