Parses an XML input file given a specified identifier of tags to be loaded.
The output is a bag of XML elements where each element is returned as
a chararray containing the text of the matched XML element including the
start and tags as well as the data between them. In case of nesting elements
of the matching tags, only the top level one is returned.
Initializes LoadFunc for reading data. This will be called during execution
before any calls to getNext. The RecordReader needs to be passed here because
it has been instantiated for a particular InputSplit.
This will be called during planning on the front end. This is the
instance of InputFormat (rather than the class name) because the
load function may need to instantiate the InputFormat in order
to control how it is constructed.
Communicate to the loader the location of the object(s) being loaded.
The location string passed to the LoadFunc here is the return value of
LoadFunc.relativeToAbsolutePath(String, Path). Implementations
should use this method to communicate the location (and any other information)
to its underlying InputFormat through the Job object.
This method will be called in the frontend and backend multiple times. Implementations
should bear in mind that this method is called multiple times and should
ensure there are no inconsistent side effects due to the multiple calls.