|Oracle® XML Developer's Kit Programmer's Guide
10g Release 1 (10.1)
Part Number B10794-01
This chapter contains these topics:
Unified C++ APIs for XML tools represent a set of C++ interfaces for Oracle XML tools. This unified approach provides a generic, interface-based framework that allows XML tools to be improved, updated, replaced, or added without affecting any interface-based user code, and minimally affecting application drivers and, possibly, application configuration. All three kinds of C++ interfaces: abstract classes, templates, and implicit interfaces represented by generic template parameters, are used by the unified framework.
Note:Use the new unified C++ API in
These C++ APIs support the W3C specification as closely as possible; however, Oracle cannot guarantee that the specification is fully supported by our implementation because the W3C specification does not cover C++ implementations.
The C++ interface is provided with the database and the Oracle Application Server and is also available for download from the OTN site:
Sample files are located at
readme.html in the root directory of the software archive contains release specific information including bug fixes and API additions.
Ctx - namespace for TCtx related declarations
Dom - namespace for DOM related declarations
Parser - namespace for parser and schema validator declarations
IO - namespace for input and output source declarations
Xsl - namespace for XSLT related declarations
XPath- namespace for XPath related declarations
Tools - namespace for Tools::Factory related declarations
OracleXml is fully defined in the file
xml.hpp. Another namespace,
XmlCtxNS, visible to users, is defined in
xmlctx.hpp. That namespace contains C++ definitions of data structures corresponding to C level definitions of the
xmlctx context and related data structures. While there is no need for users to know details of that namespace,
xmlctx.hpp needs to be included in most application main modules.
Multiple encodings are currently supported on the base of the
oratext type that is currently supposed to be used by all implementations. All strings are represented as
The Ctx namespace contains data types and interfaces related to the TCtx interface.
DATATYPE encoding - a particular supported encoding. The following kinds of encodings (or encoding names) are supported:
input_encoding - overwrites the previous one
error_language - gets overwritten by the language of the error handler, if specified
DATATYPE encodings - array of encodings.
ErrorHandler Interface - This is the root error handler class. It deals with local processing of errors, mainly from the underlying C implementation. It may throw
XmlException in some implementations. But this is not specified in its signature in order to accommodate needs of all implementations. However, it can create exception objects. The error handler is passed to the
TCtx constructor when
TCtx is initialized. Implementations of this interface are provided by the user.
MemAllocator Interface - This is a simple root interface to make the
TCtx interface reasonably generic so that different allocator approaches can be used in the future. It is passed to the
TCtx constructor when
TCtx is initialized. It is a low level allocator that does not know the type of an object being allocated. The allocators with this interface can also be used directly. In this case the user is responsible for the explicit deallocation of objects (with
MemAllocator interface is passed as a parameter to the
TCtx constructor, then, in many cases, it makes sense to overwrite the operator new. In this case all memory allocations in both C and C++ can be done by the same allocator.
Tctx Interface - This is an implicit interface to XML context implementations. It is primarily used for memory allocation, error (not exception) handling, and different encodings handling. The context interface is an implicit interface that is supposed to be used as type parameter. The name
TCtx will be used as a corresponding type parameter name. Its actual substitutions are instantiations of implementations parameterized (templatized) by real context implementations. In the case of errors
XmlException might be thrown.All constructors create and initialize context implementations. In a multithreaded environment a separate context implementation has to be initialized for each thread.
IO namespace specifies interfaces for the different input and output options for all XML tools.
InputSourceType specifies different kinds of input sources supported currently. They include:
ISRC_URI - Input is to be read from the specified URI.
ISRC_FILE - Input is to be read from a file.
ISRC_BUFFER - Input is to be read from a buffer.
ISRC_DOM - Input is a DOM tree.
ISRC_CSTREAM - Input is a C level stream.
URISource - This is an interface to inputs from specified URIs.
FileSource - This is an interface to inputs from a file.
BufferSource - This is an interface to inputs from a buffer.
DOMSource - This is an interface to inputs from a DOM tree.
CStreamSource - This is an interface to inputs from a C level stream.
Tools is the package (sub-space of
OracleXml) for types and interfaces related to the creation and instantiation of Oracle XML tools.
Error message files are provided in the
mesg subdirectory. The messages files also exist in the
$ORACLE_HOME/xdk/mesg directory. You can set the environment variable
ORA_XML_MESG to point to the absolute path of the
mesg subdirectory, although this not required.
See Also:Oracle XML API Reference