XPATH - navigating to a specific repeatable elements value

Question

Hi out there!
Currently I have a problem in evaluating some XPath for a bunch of corresponding node sets. Maybe someone can help me.
I would like to get the field value of the bold market field ( 2 ) in just that CargoSet.
The only things I will know from the start are, as the file will be generated automatically:
- name: OverallSet
- name: CargoSet
- name: field1
I dont know how to cope with it yet.
There are just 4 things, u should keep in mind:
* Segment1 is repeatable n times
* CargoSet can be repeated in Segment1 n times
* Every CargoSet contains field1 exactly 1 time
* the name of Segment1 is unknown
I would be glad, if someone could help me going on... Or is XPATH totally underpowered for that demands, as there can be no iterative processes build in XPATH?
Thanks in advance!
Jens
<?xml version="1.0" encoding="UTF-8"?>
<OverallSet>
                <Segment1>
                                <CargoSet>
                                               <field1>1</field1>
                                               <field2>Y</field2>
                                               <field3>X</field3>
                                               <field4/>
                                </CargoSet>
                                <CargoSet>
                                               <field1>2</field1>
                                               <field2>A</field2>
                                               <field3>B</field3>
                                               <field4/>
                                </CargoSet>
                                <CargoSet>
                                                <field1>3</field1>
                                                <field2/>
                                                <field3>Q</field3>
                                                <field4/>
                               </CargoSet>
               </Segment1>
               <Segment1>
                                <CargoSet>
                                                <field1>1</field1>
                                                <field2>L</field2>
                                                <field3>M</field3>
                                                <field4/>
                               </CargoSet>
                                <CargoSet>
                                                 <field1>2</field1>
                                                 <field2>K</field2>
                                                 <field3>A</field3>
                                                 <field4>S</field4>
                               </CargoSet>
               </Segment1>
</OverallSet>

Answer 1

//Specify the variable Segment1
String Segment1=argv[0];
the field 1 in the second CargoSet of the first Segment1
String xpath="/OverallSet/"+Segment1+"[1]"+"/CargoSet[2]/field1";