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JAXP 1.3 Release Notes - JDK 5 Documentation v1.5.0, Java 2 SDK 英文文档

JavaTM API for XML Processing Release Notes

Specification Version: 1.3
Reference Implementation (RI) Version: 1.3.0

This document contains installation instructions and other notes that may help you use this software library more effectively. See also the JAXP FAQ for more information.

Note:
If you are reading this page online, this is the most current version of the release notes. If this page was downloaded as part of the release bundle, please see the JAXP Documentation page for the most current version of the release notes.

Contents

Component Versions

These versions of the relevant technologies have been incorporated into the reference implementation.

Identifying the JAR Files

This release is contained in six JAR files:

jaxp-api.jar
The javax.xml.parsers, javax.xml.transform, javax.xml.xpath, javax.xml.validation, javax.xml.datatype, and javax.xml.namespace components of JAXP. These packages contain the APIs that give applications a consistent way to obtain instances of XML processing implementations.  The javax.xml.xpath package supports the standard XPath API.
sax.jar
The APIs and helper classes for the Simple API for XML (SAX), used for serial access to XML data.  The APIs support SAX version 2.0.2.
dom.jar
The APIs and helper classes for the Document Object Model (DOM), used to create an in-memory tree structure from the XML data.  The APIs support DOM Level 3.
xercesImpl.jar
The implementation classes for the SAX and DOM parsers, as well as Xerces-specific implementations of the JAXP APIs..
 
xalan.jar
Contains XSLTC the compiling XSLT processor from the Xalan project.

XML Parsing

The information in this section pertains to the Xerces technology. The latest updates can be found at http://jaxp.dev.java.net.  For information on known bugs and recent fixes in the latest Apache version, see http://xml.apache.org/xerces2-j/releases.html. 

Known Schema Processing Limitations

This section discusses known schema processing bugs, limitations, and implementation-dependent operations.

Limitations

These limitations specify known upper bounds on values.

Implementation-Dependent Operations

This implementation-dependent operation is not fully clarified by the W3C XML Schema specification (http://www.w3.org/2001/XMLSchema). As a result, differing implementations exist.

Known Migration Issues

This section covers known issues that arise when migrating from earlier versions of JAXP.

Migrating from JAXP 1.2

JAXP 1.2 is built into JWSDP and J2EE 1.4. These sections of the Compatibility Guide cover the relevant migration issues:

Migrating from JAXP 1.1

JAXP 1.1 is built into J2EE 1.3 and J2SE 1.4. For differences in functionality from JAXP 1.1, see the JAXP Compatibility Guide.

DOM Level 3 Implementation Notes

This section contains implementation notes for DOM Level 3 Core and DOM Level 3 Load and Save.

DOM Level 3 Core

Not implemented:

Supported parameters:

DOM Level 3 Load and Save

Not supported:

The Compiling XSLT Processor (XSLTC)

The XSLTC transformer generates a transformation engine, or translet, from an XSL stylesheet. This approach separates the interpretation of stylesheet instructions from their runtime application to XML data.

XSLTC works by compiling a stylesheet into Java byte code (translets), which can then be used to perform XSLT transformations. This approach greatly improves the performance of XSLT transformations where a given stylesheet is compiled once and used many times. It also generates an extremely lightweight translet, because only the XSLT instructions that are actually used by the stylesheet are included.

Note:
XSLT is supported by the JAXP transform package. See javax.xml.transform for details on accessing basic XSLT functionality in an implementation-independent manner.

Custom Class Loader Issue

A problem can occur when using a custom class loader with a transformation factory.

Transformation factories in JAXP always prefer the use of the "context class loader" to the use of the "system class loader". Thus, if an application uses a custom class loader, it may need to set the custom class loader as the context class loader for transformation factory to use it. Setting a custom class loader on the current thread can be done as follows:

try {
  Thread currentThread = Thread.currentThread();
  currentThread.setContextClassLoader(customClassLoader);
}
catch (SecurityException e) {
  // ...
}

If the application is multi-threaded, the custom class loader may need to be set in all threads (every time a new thread is created). A security exception is thrown if an application does not have permission to set the context class loader.

JWSDP Security Considerations

When an application is running on a web server, such as the Java Web Services Developer Pack (JWSDP), with security enabled, the following permissions must be set:

permission java.io.FilePermission

    "/${webserver.home}/common/endorsed/xercesImpl.jar", "read";
permission java.io.FilePermission
    "/${webserver.home}/common/endorsed/xalan.jar", "read";

permission java.util.PropertyPermission
    "javax.xml.parser.SAXParserFactory", "read, write";
permission java.util.PropertyPermission
    "javax.xml.transform.TransformerFactory", "read, write";

permission java.util.PropertyPermission "user.dir",        "read";
permission java.util.PropertyPermission "file.separator",  "read";
permission java.util.PropertyPermission "line.separator",  "read";
permission java.util.PropertyPermission "JavaClass.debug", "read";

permission java.lang.RuntimePermission "createClassLoader";
permission java.lang.RuntimePermission "accessDeclaredMembers";

Note:
If read permission is not set for xercesImpl.jar, a FactoryConfigurationError is thrown that says:
   Provider org.apache.xerces.jaxp.SAXParserFactoryImpl not found

Changes in JAXP RI Versions

Changes in JAXP RI version 1.3

Changes in JAXP RI version 1.2.4

Changes in JAXP RI version 1.2.3

Changes in JAXP RI version 1.2.2

Changes in JAXP Ri version 1.2.1

Performance of Xerces parser improved significantly.

XSLTC was not included as part of this release, which was destined solely for the J2EE platform. 

Changes in JAXP RI version 1.2.0-FCS

The parser implementation changed from Xerces 2.0.0_01 to Xerces-J 2.0.1_01
(Xerces 2.0.1 final with controlled bug fixes). The Xalan XSLT processor
implementation was updated to xalan-j 2.3.1_01 (Xalan version 2.3.1 with
controlled bug fixes).

Finally, this release fully supports the proposed 1.2 JAXP specification,
which implements document validation using W3C XML Schema.

Changes In JAXP RI version 1.2.0-EA2

The parser implementation changed from Xerces 2.0.0 beta3 to Xerces-J 2.0.0_01 (Xerces 2.0.0 final with controlled bug fixes). The Xalan XSLT processor implementation was updated to xalan-j 2.3.0_01 (Xalan version 2.3.0 with controlled bug fixes).

The Xalan XSLTC processor was also added in this release. (It is used to compile a stylesheet into a transformation engine (translet) that is ready to run.)

This release fully supports the proposed 1.2 JAXP specification, which implements document validation using W3C XML Schema.

Changes in JAXP RI version 1.2.0-EA1

The parser implementation changed from Apache Crimson to Xerces 2 version 2.0.0 beta3. The XSLT processor implementation was updated to Xalan classic version 2.2.D14.

The parser supports W3C XML Schema but does not support all aspects of the proposed JAXP 1.2 specification. In particular, the ability to enforce that an instance document conforms to a particular schema has not been implemented. However, the validation portions of the specification can be used along with schema hints in the instance document.