Replacing the element's attribute in sequential order

Hi,

I have few xml files (depends on user how much he/she wants to pass). I
have to take those files and merge them, so I have created a loop and in
that I am passing these files one by one. For this I have written few rules
to merge. But there is this <Procedure> tag where I am stuck. To merge this
I need to parse each Procedure and have to modify its attributes (attrProc
and attrLevel). I have to replace the attrProc attribute with a sequential
value and for me this will set a unique "Level" for each Procedure tag and
later I will process them based on their level.


*File1.xml*

*<?xml version="1.0" encoding="UTF-8"?>*
*<InfoTag>*
*<Procedure attrProc="TestProcA" attrLevel="1">*
*      <downTime>*
*        <acceptableDownTime>*
*          <all/>*
*        </acceptableDownTime>*
*        <downTimePeriod time="600000000"/>*
*      </downTime>*
*    </Procedure>*

* <Procedure attrProc="TestProcB" attrLevel="2">*
*      <downTime>*
*        <acceptableDownTime>*
*          <all/>*
*        </acceptableDownTime>*
*        <downTimePeriod time="600000000"/>*
*      </downTime>*
*    </Procedure>*
*</InfoTag>*


*File2.xml*

*<?xml version="1.0" encoding="UTF-8"?>*
*<InfoTag>*
*<Procedure attrProc="TestProcC" attrLevel="3">*
*      <downTime>*
*        <acceptableDownTime>*
*          <all/>*
*        </acceptableDownTime>*
*        <downTimePeriod time="600000000"/>*
*      </downTime>*
*    </Procedure>*

* <Procedure attrProc="TestProcD" attrLevel="4">*
*      <downTime>*
*        <acceptableDownTime>*
*          <all/>*
*        </acceptableDownTime>*
*        <downTimePeriod time="600000000"/>*
*      </downTime>*
*    </Procedure>*
*</InfoTag>*


I am trying to fetch an output file which looks like this:

*Output.xml*

*<InfoTag>*
*<Procedure attrProc="1" attrLevel="### NOT UNIQUE ###">*
*      <downTime>*
*        <acceptableDownTime>*
*          <all/>*
*        </acceptableDownTime>*
*        <downTimePeriod time="600000000"/>*
*      </downTime>*
*    </Procedure>*
* <Procedure attrProc="2" attrLevel="### NOT UNIQUE ###">*
*      <downTime>*
*        <acceptableDownTime>*
*          <all/>*
*        </acceptableDownTime>*
*        <downTimePeriod time="600000000"/>*
*      </downTime>*
*    </Procedure>*
*<Procedure attrProc="3" attrLevel="### NOT UNIQUE ###">*
*      <downTime>*
*        <acceptableDownTime>*
*          <all/>*
*        </acceptableDownTime>*
*        <downTimePeriod time="600000000"/>*
*      </downTime>*
*    </Procedure>*
* <Procedure attrProc="4" attrLevel="### NOT UNIQUE ###">*
*      <downTime>*
*        <acceptableDownTime>*
*          <all/>*
*        </acceptableDownTime>*
*        <downTimePeriod time="600000000"/>*
*      </downTime>*
*    </Procedure>    *
*</InfoTag>*


I am thinking of looping it and will count the occurrences of it and then I
am thinking to replace the value. But I am not able to do that.
Can anyone tell me how to achieve this. How can I loop every Procedure tag
and and append the attrProc attribute value in a sequential order?

Thanks,
BR,
Varun