Many utilities output their processing results as XML files (e.g. Checkstyle, FindBugs). It would be useful if there was a post-processor that allowed these files to be handled in a better manner than is possible with the regex post processor.

The post-processor could be configured using XPath expressions to both identify errors and warnings in the XML file and format a summary message indicating the problem.

e.g. to process:

<checkstyle version="4.1">
  <file name="/data/pulse/data/recipes/1802308/base/cart/src/main/java/org/acme/epv/cart/CartUnavailableException.java">
    <error line="16" column="5" severity="warning" message="Missing a Javadoc comment."
      source="com.puppycrawl.tools.checkstyle.checks.javadoc.JavadocVariableCheck"/>
  </file>
  <file name="/data/pulse/data/recipes/1802308/base/cart/src/main/java/org/acme/epv/cart/ShoppingCartService.java">
  </file>
  <file name="/data/pulse/data/recipes/1802308/base/cart/src/main/java/org/acme/epv/cart/ShoppingCartException.java">
  </file>
</checkstyle>

You could use something like:

<xml.pp>
  <xpath category="warning"
    select="//file/error[@severity='warning']"
    summary="[Checkstyle] \${../@name} \${@line}:\${@column} - \${@message}"/>
</xml.pp>

To provide output of:
[Checkstyle] /data/pulse/data/recipes/1802308/base/cart/src/main/java/org/acme/epv/cart/CartUnavailableException.java 16:5 - Missing a Javadoc comment.