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ISQLXML Interface

Definition

The mapping in the JavaTM programming language for the SQL XML type.

[Android.Runtime.Register("java/sql/SQLXML", "", "Java.Sql.ISQLXMLInvoker")]
public interface ISQLXML : Android.Runtime.IJavaObject, IDisposable, Java.Interop.IJavaPeerable
[<Android.Runtime.Register("java/sql/SQLXML", "", "Java.Sql.ISQLXMLInvoker")>]
type ISQLXML = interface
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable
Attributes
Implements

Remarks

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.

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.

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.

The XML value of the SQLXML instance may be obtained as a BinaryStream using

SQLXML sqlxml = resultSet.getSQLXML(column);
              InputStream binaryStream = sqlxml.getBinaryStream();

For example, to parse an XML value with a DOM parser:

DocumentBuilder parser = DocumentBuilderFactory.newInstance().newDocumentBuilder();
              Document result = parser.parse(binaryStream);

or to parse an XML value with a SAX parser to your handler:

SAXParser parser = SAXParserFactory.newInstance().newSAXParser();
              parser.parse(binaryStream, myHandler);

or to parse an XML value with a StAX parser:

XMLInputFactory factory = XMLInputFactory.newInstance();
              XMLStreamReader streamReader = factory.createXMLStreamReader(binaryStream);

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.

For example, to obtain a DOM Document Node:

DOMSource domSource = sqlxml.getSource(DOMSource.class);
              Document document = (Document) domSource.getNode();

or to set the value to a DOM Document Node to myNode:

DOMResult domResult = sqlxml.setResult(DOMResult.class);
              domResult.setNode(myNode);

or, to send SAX events to your handler:

SAXSource saxSource = sqlxml.getSource(SAXSource.class);
              XMLReader xmlReader = saxSource.getXMLReader();
              xmlReader.setContentHandler(myHandler);
              xmlReader.parse(saxSource.getInputSource());

or, to set the result value from SAX events:

SAXResult saxResult = sqlxml.setResult(SAXResult.class);
              ContentHandler contentHandler = saxResult.getXMLReader().getContentHandler();
              contentHandler.startDocument();
              // set the XML elements and attributes into the result
              contentHandler.endDocument();

or, to obtain StAX events:

StAXSource staxSource = sqlxml.getSource(StAXSource.class);
              XMLStreamReader streamReader = staxSource.getXMLStreamReader();

or, to set the result value from StAX events:

StAXResult staxResult = sqlxml.setResult(StAXResult.class);
              XMLStreamWriter streamWriter = staxResult.getXMLStreamWriter();

or, to perform XSLT transformations on the XML value using the XSLT in xsltFile output to file resultFile:

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);

or, to evaluate an XPath expression on the XML value:

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);

To set the XML value to be the result of an XSLT transform:

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);

Any Source can be transformed to a Result using the identity transform specified by calling newTransformer():

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);

To write the contents of a Source to standard output:

Transformer identity = TransformerFactory.newInstance().newTransformer();
              Source source = sqlxml.getSource(null);
              Result result = new StreamResult(System.out);
              identity.transform(source, result);

To create a DOMSource from a DOMResult:

DOMSource domSource = new DOMSource(domResult.getNode());

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.

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.

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.

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.

All methods on the SQLXML interface must be fully implemented if the JDBC driver supports the data type.

Added in 1.6.

Java documentation for java.sql.SQLXML.

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Properties

BinaryStream

Returns a stream that can be used to read binary data from this SQL XML object.

CharacterStream

Returns a reader that can be used to read character data from this SQL XML object.

Handle

Gets the JNI value of the underlying Android object.

(Inherited from IJavaObject)
JniIdentityHashCode

Returns the value of java.lang.System.identityHashCode() for the wrapped instance.

(Inherited from IJavaPeerable)
JniManagedPeerState

State of the managed peer.

(Inherited from IJavaPeerable)
JniPeerMembers

Member access and invocation support.

(Inherited from IJavaPeerable)
PeerReference

Returns a JniObjectReference of the wrapped Java object instance.

(Inherited from IJavaPeerable)
String

Returns this object's data as an XML string.

Methods

Disposed()

Called when the instance has been disposed.

(Inherited from IJavaPeerable)
DisposeUnlessReferenced()

If there are no outstanding references to this instance, then calls Dispose(); otherwise, does nothing.

(Inherited from IJavaPeerable)
Finalized()

Called when the instance has been finalized.

(Inherited from IJavaPeerable)
Free()

This method closes this object and releases the resources that it held.

GetSource(Class)

Returns a Source for reading the XML value designated by this SQLXML instance.

SetBinaryStream()

Retrieves a stream that can be used to write the XML value that this SQLXML instance represents.

SetCharacterStream()

Retrieves a stream to be used to write the XML value that this SQLXML instance represents.

SetJniIdentityHashCode(Int32)

Set the value returned by JniIdentityHashCode.

(Inherited from IJavaPeerable)
SetJniManagedPeerState(JniManagedPeerStates) (Inherited from IJavaPeerable)
SetPeerReference(JniObjectReference)

Set the value returned by PeerReference.

(Inherited from IJavaPeerable)
SetResult(Class)

Returns a Result for setting the XML value designated by this SQLXML instance.

UnregisterFromRuntime()

Unregister this instance so that the runtime will not return it from future Java.Interop.JniRuntime+JniValueManager.PeekValue invocations.

(Inherited from IJavaPeerable)

Extension Methods

JavaCast<TResult>(IJavaObject)

Performs an Android runtime-checked type conversion.

JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to