JDK-8011653: Upgrade to JAXP 1.5

[Daniel Fuchs]

Hi Joe,

I am not a JAXP expert - so I've been discovering most
of this code as I read it. It would be impossible for me
to assess whether there's some setFeature or setProperty
missing somewhere for instance. So with my limited
knowledge I have only these few remarks:


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1. XalanConstants.java: javadoc ORACLE_FEATURE_SERVICE_MECHANISM:

"instructs the implementation to use service mechanism to find 
implementation"

That sounds a bit cryptic to my ears. Would something like:

   "true:  instruct an object to use service mechanism to
           find a service implementation"

   "false: instruct an object to skip service mechanism and
           use the default implementation for that service"

work better? (disclaimer: I am not a native English speaker.)

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2. 
<http://cr.openjdk.java.net/~joehw/jdk8/8011653/webrev/src/com/sun/org/apache/xerces/internal/impl/XMLDocumentFragmentScannerImpl.java.frames.html>

  773         //JAXP 1.5 properties
  774         if 
(propertyId.startsWith(Constants.JAXPAPI_PROPERTY_PREFIX)) {
  775             if (propertyId.equals(ACCESS_EXTERNAL_DTD))
  776             {
  777                 fAccessExternalDTD = (String)value;
  778             }
  779         }


The first line (startsWith(...) seems useless.
When I saw this lines of code - I first thought there was a
bug - expecting ACCESS_EXTERNAL_DTD to be a suffix like
in the lines just before.

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3. Same remark than 2. with:
<http://cr.openjdk.java.net/~joehw/jdk8/8011653/webrev/src/com/sun/org/apache/xerces/internal/impl/XMLEntityManager.java.frames.html>

(lines 1643-1650)


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4. same class as above: what is the story with this
    "Zephyr feature ignore-external-dtd" ?

   Namely I'm puzzled as to why in one case we check only
   the Zephyr feature, and in another case we check only the
   Xerces feature.

   Shouldn't both be checked?

   I mean - are we sure that nobody can call something like:

       PropertyManager propertyManager = ...;
       propertyManager.setFeature(LOAD_EXTERNAL_DTD, false);


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-- daniel