== Changes from 3.0.x to 4.0.x ==

=== Stream reader ===

* Defaulting reporting of "no prefix" and "no namespace [URI]"
  have been changed from null value to empty Strig (""), to be
  in accordance with the latest consensus regarding Stax API.
* Fix for [WSTX-140] changes default for IS_COALESCING to be
  Boolean.FALSE as per Stax specs. 3.0 and earlier were defaulting
  to Boolean.TRUE.
* XMLStreamReader.getProperty() will no longer throw IllegalArgumentException,
  if fed an unknown property name. Rather, null is returned.
  This is thought to be Stax 1.0 compliant, and both more convenient
  and performant for cases where application needs to offer interoperability
  with multiple Stax implementations.

=== Stream writer ===

* Default setting of WstxOutputProperties.P_OUTPUT_FIX_CONTENT was
  true in 3.x. While this seemed like a good idea for maximum xml
  conformance, it also causes incompatibility issue with the JDK 6
  included Sun Stax implementation, which does not implement either
  well-formedness checks or fixing algorithm. As a result, something
  that works well with Woodstox would not necessarily work well with
  JDK6 default Stax implementation.
  As a result, *WstxOutputProperties.P_OUTPUT_FIX_CONTENT* was
  default settings was *changed to false*.

=== Validation ===

* Validation methods now consistently allow throwing of XMLStreamException
  instead of limiting it to just XMLValidationException.
  The reason is that due to call chaining, XMLReporter (which allows throwing
  of generic stream exception) may be called from within validation
  problem reporting methods, and resulting exceptions must
  be let pass through call stack (see [WSTX-154] for details).

== Changes from 2.0.x to 3.0.x ==

=== XML compatibility ===

* 3.0 now supports xml 1.1 cleanly (is aware of differences between 1.0,
  uses separate well-formedness checks where necessary)
* XML conformance significantly improved, to pass XMLTest test suite
  (with 99%+ pass rate).

=== Packaging ===

* EscapingWriterFactory moved from main org.codehaus.stax2 package
  to the new org.codehaus.stax.io sub-package.

=== Stream reader ===

* Default setting for P_REPORT_PROLOG_WHITESPACE is
  now Boolean.TRUE (instead of Boolean.FALSE), to emulate behaviour
  of the StAX reference implementation, and to keep output in pass-through
  configurations more similar to input.
* Handling of undeclared entities changed so that no exception is thrown
  in non-expanding mode; this is similar to the way ref. impl. works.
* isCharacters() now only returns true if current event is CHARACTERS,
  instead of CHARACTERS, CDATA and SPACE (as in 1.0 and 2.0). Change was
  done for interoperatibility -- the StAX reference implementation
  behaves like 3.0.
* Removed property P_TEXT_BUFFER_LENGTH, since there is no real benefit
  from changing this setting -- text buffer is resized dynamically as
  needed, and initial value is largely irrelevant.

=== Stream writer ===

* In 2.0.x most well-formedness checks (P_CHECK_xxx) resulted in
  unchecked IllegalStateException. Due to requests by developers, who
  found this unintuitive, these were replaced by checked XMLStreamExceptions.
* In 2.0.x, WstxOutputProperties.P_OUTPUT_VALIDATE_CONTENT was false
  by default: in 3.0 it is true. Change was due to more efficient checking
  of the content, made possible by integrated transcoding. As such, it seems
  useful to have more rigorous checks enabled by default. Also, since
  WstxOutputProperties.P_OUTPUT_FIX_CONTENT was and is true by default,
  CDATA and COMMENT sections will be automatically "fixed" now.

=== Event reader ===

* Event readers are now constructed so that P_LAZY_PARSING is always
  disabled (to get accurate XMLStreamExceptions instead of possible
  runtime exceptions, with no performance difference).
  Also, P_MIN_TEXT_SEGMENT will be set to maximum value, to avoid
  ever splitting a CHARACTERS or CDATA segment (to minimize number
  of event objects created).