RFR: JDK-8008738 - Issue in com.sun.org.apache.xml.internal.serializer.Encodings causes some JCK tests to fail intermittently

[huizhe wang]

Hi Daniel,

Thanks for the detailed explanation!  The fix looks good.

Sorry for the delay.

Regards,
Joe

On 4/15/2013 7:09 AM, Daniel Fuchs wrote:
> Hi,
>
> This a fix for:
>
> JDK-8008738 - Issue in 
> com.sun.org.apache.xml.internal.serializer.Encodings causes some JCK 
> tests to fail intermittently.
>
> <http://cr.openjdk.java.net/~dfuchs/JDK-8008738/webrev.02/>
>
> The issue here is that 
> com.sun.org.apache.xml.internal.serializer.Encodings
> tries to implement a double mapping:
>
>    Java Charset Name => Preferred XML Mime Name
>
> and
>
>    XML Mime Name => Java Charset Name
>
> from a specification that it reads from an Encoding.properties file.
>
> However, there can be several 'Java' names (aliases) corresponding to
> a given Charset, and there could also be several XML Mime Names,
> corresponding to that same charset.
>
> The Encodings.properties files uses 'Java Names' as keys, which it
> can map to one - or more - XML mime names, where the first XML name
> in the list stands for the 'preferred' mime name.
>
> The trouble is that some of the Java names present in the
> Encodings.properties files are not recognized by the Charset API,
> although some of the corresponding XML mime names, can be.
>
> This resulted in the creation of EncodingInfo objects whose charset
> name was not recognized by the Charset API. However, since there can
> be several Java Names specified with the same XML name, this did
> not always lead to errors:
> when 'converting' an XML name to a Java Name, if the first
> mapping picked up had a recognized Java Name - everything went well.
> If however - the first mapping picked up had an unrecognized Java Name,
> then this lead to failure to encode characters properly.
> Since the order in which the EncodingInfo where registered depended on
> the order of keys/values returned by HashMap/Properties - it could
> work in one run and fail in another.
>
> The proposed changeset is reworking the algorithm that
> creates EncodingInfo objects and perform the mapping
> Java Name <-> Mime Name:
>
> * Parse the whole line and consider both Java Names & Mime Names when
>   trying to instantiate EncodingInfo objects for a Java Name,
> * Make sure the javaName recorded in EncodingInfo is one that is
>   recognized by Charset.forName().
>
> The changeset has a unit test (under jdk/test/javax/xml/jaxp) which
>
> 1. verifies that the Encodings.properties file has no inconsistencies
>
> 2. verifies the mapping implemented by Encodings.java - by calling
>    Encodings.convertMime2JavaEncoding(<Mime Name>) and
>    Encodings.getMimeEncoding(<Java Name>)
>    (skipping those names for which no charset could be loaded, as
>    not all charset are necessarily available on all machines).
>
> -- daniel
>
>
>