tXMLMap

tXMLMap properties

Component family	Processing/XML
Function	tXMLMap is an advanced component fine-tuned for transforming and routing XML data flow (data of the Document type), especially when processing numerous XML data sources, with or without flat data to be joined.
Purpose	tXMLMap transforms and routes data from single or multiple sources to single or multiple destinations.
Basic settings	Map editor	It allows you to define the tXMLMap routing and transformation properties.
Advanced settings	tStatCatcher Statistics	Select this check box to gather the Job processing metadata at the Job level as well as at each component level.
Global Variables	ERROR_MESSAGE: the error message generated by the component when an error occurs. This is an After variable and it returns a string. This variable functions only if the Die on error check box is cleared, if the component has this check box. A Flow variable functions during the execution of a component while an After variable functions after the execution of the component. To fill up a field or expression with a variable, press Ctrl + Space to access the variable list and choose the variable to use from it. For further information about variables, see Talend Studio User Guide.
Usage	Possible uses are from a simple reorganization of fields to the most complex jobs of data multiplexing or demultiplexing transformation, concatenation, inversion, filtering and so on. When needs be, you can define sophisticated outputting strategy for the output XML flows using group element, aggregate element, empty element and many other features such as All in one. For further information about these features, see Talend Studio User Guide. It is used as an intermediate component and fits perfectly the process requiring many XML data sources, such as, the ESB request-response processes.
Log4j	The activity of this component can be logged using the log4j feature. For more information on this feature, see Talend Studio User Guide. For more information on the log4j logging levels, see the Apache documentation at http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/Level.html.
Limitation	The limitations to be kept in mind are: – The use of this component supposes minimum Java and XML knowledge in order to fully exploit its functionalities. – This component is a junction step, and for this reason it cannot be a start nor an end component in the Job. – At least one loop element is required for each XML data flow involved.

The following sections present several generic use cases about how
to use the tXMLMap component, while if you need some
specific examples using this component along with the ESB components to build data services, see the scenarios for the
ESB components:

If you need further information about the principles of mapping multiple input and
output flows, see Talend Studio User
Guide.

Scenario 1: Mapping and transforming XML data

In this scenario, a three-component Job is run to map and transform data from one XML
source file customer.xml, and generate an XML output flow which
could be reused for various purposes in the future, such as for an ESB request.

These three components are:

tFileInputXML: this component is used to
provide input data to tXMLMap.
tXMLMap: this component maps and transforms
the received XML data flows into one single XML data flow.
tLogRow: this component is used to display
the output data.

To replicate this scenario, proceed as the following sections illustrate.

Dropping and linking the components

To do this, proceed as follows:

From the Palette, drop tFileInputXML, tXMLMap and tLogRow into
the Design workspace.

Note

A component used in the workspace can be labelled the way you need. In
this scenario, this input component is labelled
Customers for tFileInputXML. For further information about how to
label a component, see Talend Studio User
Guide.
Right-click the tFileInputXML component
labelled Customers to open its contextual menu.
From this menu, select Row
>
Main link to connect this component to
tXMLMap.
Repeat this operation to connect tXMLMap
to tLogRow using Row > *New Output*
(Main) link. A pop-up dialog box prompts you to name this
output link. In this scenario, name it as
Customer.

Then you can continue to configure each component.

Configuring the input flow

To do this, proceed as follows:

Double-click the tFileInputXML component
labelled Customers to display its Basic settings view.
Next to Edit schema, click the three-dot
button to open the schema editor.
In the schema editor, click the plus button to add one row.
In the Column column, type in a new name
for this row. In this scenario, it is Customer.
In the Type column, select the data type
of this row. In this scenario, it is Document. The
document data type is essential for making full use of tXMLMap. For further information about this data type, see
Talend Studio User
Guide.
Click OK to validate this editing. One
row is added automatically to the Mapping
table.
In the File name/Stream field, browse to
or type in the path to the XML source that provides the customer data. In
this scenario, it is “E:/Studio/Customer.xml”.
In the Loop XPath query field, type in
"/" to replace the default one. This means the source data
is queried from the root.
In the XPath query column of the
Mapping table, type in the XPath. In
this scenario, type in ".", meaning that all of the data from
source are queried.
In the Get Nodes column of the Mapping table, select the check box.

Note

In order to build the Document type
data flow, it is necessary to get the nodes from this component.

Configuring tXMLMap for transformation

To do this, proceed as follows:

Double-click the tXMLMap component to
open the Map Editor.

Note that the input area is already filled with the defined input tables
and that the top table is the main input table.
In the left table, right-click Customer
to open the contextual menu.
From this contextual menu, select Import From
File and in the pop-up dialog box, browse to the
corresponding source file in order to import therefrom the XML structure
used by the data to be received by tXMLMap.
In this scenario, the source file is Customer.xml,
which is the data input to tFileInputXML
(Customers).

Note

You can also import an XML tree from an XSD file. When importing
either an input or an output XML tree structure from an XSD file, you
can choose an element as the root of your XML tree. For more information
on importing an XML tree from an XSD file, see Talend Studio User Guide.
In the imported XML tree, right-click the Customer
node and select As loop element to set it
as the loop element.
On the lower part of this map editor, click the Schema editor tab to display the corresponding view.
On the right side of this view, click the plus button to add one row to
the Customer table and rename this row as
Customer_States.
In the Type column of this
Customer_States row, select Document as the data type. The corresponding XML root is
added automatically to the top table on the right side which represents the
output flow.
On the right side in the top table labelled Customer,
import the XML data structure that you need to use from the corresponding
XML source file. In this scenario, it is
Customer_State.xml.
Right-click the customer node and select As loop element from the contextual menu.

Then you can begin to map the input flow to the output flow.
In the top table on the input side (left) of the map editor, click
the id node and drop it to the Expression column in the row corresponding to the
output row you need map. In this scenario, it is the
@id node.
Do the same to map CustomerName to
CustomerName, CustomerAddress
to CustomerAddress and idState to
idState from the left side to the right
side.

Note

In the real project, you may have to keep empty elements in your
output XML tree. If so, you can use tXMLMap to manage them. For further information about
how to manage empty elements using tXMLMap, see Talend Studio User Guide.
If required to generate single XML flow, click the wrench icon on top of
the output side to open the setting panel and set the All in one feature as true.
In this example, this option is set as true. For further information about the All in one feature, see Talend Studio
User Guide.
Click OK to validate the mappings and
close the Map Editor.

Note

If you close the Map Editor without
having set the required loop elements as described earlier in this
scenario, the root element will be automatically set as loop
element.

Then you can run this Job.

Configuring tLogRow to display the customer information

Double-click the tLogRow component to
open its Basic settings view.
Click Sync columns button to retrieve the
schema from its preceding component.

Executing the Job

Press Ctrl+S to save the Job.
Press F6 to execute the Job.

The customer information transformed will be displayed on the
console.

Scenario 2: Launching a lookup in a second XML flow to join complementary
data

Based on the previous scenario, this scenario shows how to use lookup in an XML flow
to join the data of interest to a given XML flow. The XML data for lookup is held in the
USStates.xml file.

To do this, another tFileInputXML component is added
to the previous Job in order to load and send the complementary data to tXMLMap. Thus this Job looks like as follows:

To replicate this scenario, proceed as the following sections illustrate.

Configuring the data flow for lookup

To do this, proceed as follows:

From the Palette, drop tFileInputXML into the Design workspace.

Note

A component used in the workspace can be labelled the way you need. In
this scenario, the newly added tFileInputXML is labelled USstates.
For further information about how to label a component, see Talend Studio User Guide.
Double-click the tFileInputXML component
labelled USStates to open its contextual menu and
select Row > Main connection to connect this component to tXMLMap. As you create this connection in the
second place, this connection is of type Lookup.
Double-click the tFileInputXML component
labelled USStates to open its Basic settings view.
Next to Edit schema, click the three-dot
button to open the schema editor.
Click the plus button to add one row and rename it to
USState.
In the Type column, select the Document option from the drop-down list.
Click OK to validate this editing.
In the File name/Stream field, browse to
or type in the path to the USStates.xml file.

Note

The input schemas could be stored in the Metadata node of the Repository tree view for easy retrieval. For further
information regarding metadata creation in the Repository, see Talend Studio User Guide.
In the Loop XPath query field, type in
"/" to replace the default value. This means the loop is
based on the root.
In the Mapping table, where one row is
already added automatically, enter "." in the XPath query column to retrieve US States data
from the source file.
In the Get Nodes column, select the check
box. This retrieves the XML structure for the Document type data.

Configuring the transformation

To do this, proceed as follows:

Double-click the tXMLMap component to
open the Map Editor.

Note that the input area is already filled with the defined input tables
and that the top table is the main input table.
Right-click USState in the lookup input
table to open its contextual menu.
From the contextual menu, select Import From
File and in the pop-up dialog box, browse to the
corresponding source file in order to import therefrom the XML structure
used by the data to be received by tXMLMap.
In this scenario, the source file is USStates.xml, which is the data input of the tFileInputXML component labelled USStates.
Right-click the States node and select
As loop element from the contextual
menu.
In the main input table, click the idState node and
drop it, in the lookup input table, to the Exp.key column in the row corresponding to the
idState row. This creates a join between the two
tables on the idState data, among which the
idState node from the main flow provides the lookup
key.

Then you can begin to modify the mapping you have done in the previous
scenario to join the complementary data into the input flow. This mapping
then should look like as follows:
In the lookup table on the input side
(left) of the map editor, click the LabelState row and
drop it on the customer node on the output side. A
dialog box pops up.
In this dialog box, select Create as sub-element of
target node and click OK.
This operation adds a new sub-element to the output XML tree and maps it
with LabelState on the input inside at the same
time.
If required to generate single XML flow, click the wrench icon on top of
the output side to open the setting panel and set the All in one feature as true.
In this example, this option is set as true. For further information about the All in one feature, see Talend Studio
User Guide.
Click OK to validate the mappings and
close the Map Editor.

Executing the Job

Press Ctrl+S to save the Job.
Press F6 to run this Job.

The Run view presents the execution
result which may read as follows:

The US state labels that correspond to the state IDs provided as the
lookup key by the main data flow are selected and outputted.

A step-by-step tutorial related to this Join topic is available on the Talend
Technical Community Site. For further information, see http://talendforge.org/tutorials/tutorial.php?language=english&idTuto=101.

Scenario 3: Mapping data using a filter

Based on Scenario 2: Launching a lookup in a second XML flow to join complementary
data, this scenario presents how to apply filter
condition(s) to select the data of interest using tXMLMap.

For example, you need to select the customer data where the state id is
9.

To replicate this scenario, proceed as follows:

In your Studio, open the Job used in the previous scenario to display it in
the Design workspace.
Double-click tXMLMap to open its editor. In
this editor, the input and output data flows have been mapped since the
replication of the previous scenario.
On the output side (right), click the button to open the filter area.
In this filter area, drop the idState node from the tree
view of the input data flow. The Xpath of idState is added
automatically to this filter area.
Still in this area, write down the filter condition of interest in Java. In
this scenario, this condition reads:
"9".equals([row1.Customer:/Customers/Customer/Address/idState])
If required to generate single XML flow, click the wrench icon on top of the
output side to open the setting panel and set the All in
one feature as true. In this
example, this option is set as true. For
further information about the All in one
feature, see Talend Studio User
Guide.
Click OK to validate this editing and close
this editor.
Press F6 to run this Job.

The execution result is displayed in the Run
view as follows:

The result says that the customer Pivot Point College is
selected as its state ID is 9, representing the
Florida state in this scenario.

Scenario 4: Catching the data rejected by lookup and filter

The data rejected by the lookup and filter conditions you set in tXMLMap can be caught and outputted by this component itself.

Based on Scenario 3: Mapping data using a filter, this scenario presents how to catch the data
rejected by the lookup and the filter set up in the previous sections.

In this scenario, another tLogRow component is added
to the Job used in the previous scenario and thus the Job displays as follows:

To replicate this scenario, proceed as follows:

In your Studio, open the Job used in the previous scenario to display it in
the Design workspace.
From the Palette, drop the tLogRow component on the workspace.
Right-click tXMLMap to open its contextual
menu and select Row > *New Output* (Main) to
connect this component to the newly added tLogRow component. A dialog box pops up to prompt you to name
this output link. In this scenario, name it as
Reject.
Click OK to validate this creation.
Double click the tXMLMap component to open
its editor. An empty Reject table has been added to the
output side to represent the output data flow carrying the rejected data. You
need to complete this table to make this editor look like as follows:
Select this empty Reject table.
In the lower part of this editor, click the Schema
editor tab to open the corresponding view.
On the right part of this Schema editor view,
click the plus button to add the rows you need to use. In this scenario, click
four times to add four rows to the Reject table.
In the Reject table presented on the right part of this
Schema editor view, rename each of the four
newly added rows. They are: ID,
Customer, idState,
LabelState.

Note

In this scenario, the Reject output flow uses flat
data type. However, you can create an XML tree view for this flow using the
Document data type. For further
information about how to use this Document
type, see Scenario 1: Mapping and transforming XML data.

The Reject table is completed and thus you have defined
the schema of the output flow used to carry the captured rejected data. Then you
need to map the data flow and set up the condition(s) to catch the rejected data
of interest.

Configuring the mapping and running the Job

In the main input table on the left side of the map editor, drag and drop
the id node to the Expression column of the corresponding row in the Reject output table.
Do the same to drag and drop CustomerName, CustomerAddress, idState
in the main input table, and LabelState
in the lookup input table to the corresponding row in the Reject output table.
On the upper part of the output side in this Map
editor, select the Reject table.
At the top of this table, click the button to open the setting area.
In the Catch Output Reject row of the
setting area, select true from the
drop-down list. Thus tXMLMap outputs the
data rejected by the filter set up in the previous scenario for the
Customer output flow.
Do the same thing to switch the Catch Lookup Inner
Join Reject row to the true
option.
Click OK to validate this editing and
close this editor.
Double-click the second tLogRow component
to open its Basic settings view.
Click Sync columns button to retrieve the
schema from its preceding component.
Press F6 to run this Job.

The captured data rejected by the filter and the lookup reads as follows
in the Run view:

None of the State IDs of these customers is 9. The
customer BBQ Smith’s Tex Mex is marked with the state
ID 60. This number does not exist in the
idState column of USStates.xml
where the defined lookup was none, so the data of this customer is rejected
by the lookup and the other data rejected by the filter.

The data selected by the filter you set up in the previous scenario reads
as follows in XML format.

Scenario 5: Mapping data using a group element

Based on the Job used in Scenario 2: Launching a lookup in a second XML flow to join complementary
data, this scenario presents how to set
up an element as group element in the Map editor of tXMLMap to
group the output data.

To replicate this scenario, you can reuse the Job in Scenario 2: Launching a lookup in a second XML flow to join complementary
data.

In this Job, double-click tXMLMap to open the
Map editor.

The objective of this scenario is to group the customer id and the customer name
information according to the States the customers come from. To do this, you need to
adjust the XML structure with considering the following factors:

The elements tagging the customer id and the customer name information should
be located under the loop element. Thus they are the sub-elements of the loop
element.
The loop element and its sub-elements should be dependent directly on the
group element.
The element tagging the States used as grouping condition should be dependent
directly on the group element.
The group element cannot be the root element.

Note

To put a group element into effect, the XML data to be processed should have been
sorted, for example via your XML tools, around the element you need to use as the
grouping condition. The figure below presents part of the sorted source data used in
this scenario. The customers possessing the same State id is already put
together.

Based on this analysis, the structure of the output data should read as
follows:

In this figure, the customers node is the root, the
Customer element is set as group
element and the output data is grouped according to the
LabelState element.

Note

To set a group element, two restrictions must be respected:

the root node cannot be set as group
element;
the group element must be the parent
of the loop element.

Once the group element is set, the first element except the loop one is used as
condition to group the output data.

To perform the adjustment according to this analysis, proceed as follows:

In the XML tree view of the output side, right-click the customer
(loop) node to open the contextual menu and select Delete. Thus all of the elements under the root
customers are removed. Then you can reconstruct the XML
tree view to have the best structure used to group the output data of
interest.
Again in the XML tree view of the output side, right-click the root node
customers to open the contextual menu and select
Create Sub-Element. Then a dialog box pops
up.
Type in the name of the new sub-element. In this scenario, it is
Customer.
Repeat the previous operations to create two more sub-elements under this
Customer node. They are:
LabelState and Name.
Do these operations again to create two more sub-elements under this newly
created Name node. They are: id and
CustomerName.
Right-click the Name node to open the contextual menu and
select As loop element to set this element as
loop.
Right-click the Customer node to open its contextual menu
and select As group element. This means that
the output data is grouped according to the LabelState
element.
From the lookup data flow on the input side, click and drop the
LabelState row to the row of the
LabelState node in the Expression column on the output side. Thus the corresponding
data is mapped.
Do the same to map the id element and the
CustomerName element between both sides. Then this
modification is done.
If required to generate single XML flow, click the wrench icon on top of the
output side to open the setting panel and set the All in
one feature as true. In this
example, this option is set as true. For
further information about the All in one
feature, see Talend Studio User
Guide.
Click OK to validate this modification and
close this editor.

Note

If you close the Map Editor without
having set the required loop elements as described earlier in this scenario,
the root element will be automatically set as loop element.
Press F6 to run this Job.

The execution result reads as follows in the Run view.

The id element and the CustomerName
element contained in the loop are grouped according to the
LabelState element. The group element
Customer tags the start and the end of each
group.
Note

tXMLMap provides group element and aggregate
element to classify data in the XML tree structure. When
handling one row of data ( one complete XML flow), the behavioral difference
between them is:
- The group element processes
  the data always within one single flow.
- The aggregate element splits
  this flow into separate and complete XML flows.

Scenario 6: Classing the output data with aggregate element

Based on the Job used in Scenario 5: Mapping data using a group element, this scenario presents how to set
up an element as aggregate element in the Map editor of tXMLMap in
order to class the output data into separate XML flows.

On the Design workspace, double-click the tXMLMap
component to open its Map editor. There the output side
reads as follows:

The objective of this scenario is to class the customer information using aggregate
element in accordance with the States they come from and then to send these classes
separately in different XML flows to the component that follows.

Note

To put an aggregate element into effect, the XML data to be processed should have
been sorted, for example via your XML tools, around the element you need to use as
the aggregating condition. The figure below presents part of the sorted source data
used in this scenario. The customers possessing the same State id is already put
together.

To do this, adjust the output XML tree as follows:

Right-click the Customer element to open its
contextual menu and from this menu, select Remove group
element.
Click the wrench icon on top of the output side to open the setting panel and
set the All in one feature as false.
Right-click the LabelState element to open
its context menu and from this menu, select As aggregate
element. This element tags the State information of each customer
and the customer information will be classed under the State information.

Note

To make the aggregate element available, ensure that the All in one feature is set as false. For further information about the
All in one feature, see Talend Studio User Guide.
Click OK to validate these changes and close
the Map editor.
Press F6 to run this Job.

Once done, the Run view is opened
automatically, where you can check the execution result.

tXMLMap outputs four separate XML flows, each of
which carries the information of one State and the customers from that State.

Note

tXMLMap provides group
element and aggregate element to
classify data in the XML tree structure. When handling one row of data ( one
complete XML flow), the behavioral difference between them is:

The group element processes the data
always within one single flow.
The aggregate element splits this
flow into separate and complete XML flows.

Scenario 7: Restructuring products data using multiple loop elements

This scenario uses a four-component Job to restructure the products data given by a
document flow using multiple loop elements.

The components used are:

tFileInputXML: it reads the source product
data and pass them to the tXMLMap
component.
tXMLMap: it transforms the input flows with
the expected structure streamlined.
tLogRow: it presents the execution result in
the console.
tFileOutputXML: it generates the output flow
into an XML file.

The input flow reads as follows:

&lt;?xml version="1.0" encoding="ISO-8859-15"?&gt;
&lt;products category="1" name="laptop"&gt;

&lt;!-- Summary --&gt;
&lt;summary&gt;
	&lt;company&gt;DELL, HP&lt;/company&gt;
	&lt;sales unit="Dollars"&gt;12345678910.12345&lt;/sales&gt;
	&lt;model&gt;business&lt;/model&gt;
&lt;/summary&gt;

&lt;!-- Loop1 manufacture --&gt;
&lt;manufacture id="manu_1" date="2012-10-30"&gt;
	&lt;name&gt;DELL&lt;/name&gt;
&lt;/manufacture&gt;
&lt;manufacture id="manu_2" date="2012-10-28"&gt;
	&lt;name&gt;HP&lt;/name&gt;
&lt;/manufacture&gt;

&lt;!-- Loop2 types --&gt;
&lt;types model="business1"&gt;
	&lt;type&gt;DELL123&lt;/type&gt;
	&lt;manufacture_id&gt;manu_1&lt;/manufacture_id&gt;
&lt;/types&gt;
&lt;types model="business2"&gt;
	&lt;type&gt;HP123&lt;/type&gt;
	&lt;manufacture_id&gt;manu_2&lt;/manufacture_id&gt;
&lt;/types&gt;
	
&lt;!-- Loop3 sale --&gt;
&lt;sales&gt;
	&lt;sale unit="Dollars" type="DELL123"&gt;
		&lt;quater&gt;1&lt;/quater&gt;
		&lt;income&gt;12345&lt;/income&gt;
	&lt;/sale&gt;
	&lt;sale unit="Dollars" type="HP123"&gt;
		&lt;quater&gt;1&lt;/quater&gt;
		&lt;income&gt;12345.123&lt;/income&gt;
	&lt;/sale&gt;
&lt;/sales&gt;
&lt;/products&gt;

<?xml version="1.0" encoding="ISO-8859-15"?>

<model>business</model>

</summary>

</manufacture>

</manufacture>

<manufacture_id>manu_1</manufacture_id>

</types>

<manufacture_id>manu_2</manufacture_id>

</types>

<sales>

</sale>

</sale>

</sales>

</products>

The objective of this restructuring is to streamline the presentation of the products
information to serve the manufacturing operations.

The output flow is expected to read as follows:

&lt;?xml version="1.0" encoding="ISO-8859-15"?&gt;
&lt;manufactures category="1" name="laptop"&gt;
  &lt;sales unit="Dollars"&gt;
    &lt;sale sales_type="DELL123"&gt;12345&lt;/sale&gt;
    &lt;sale sales_type="HP123"&gt;12345.123&lt;/sale&gt;
  &lt;/sales&gt;
  &lt;manufacture id="manu_1" date="2012-10-30" name="DELL"/&gt;
  &lt;manufacture id="manu_2" date="2012-10-28" name="HP"/&gt;
  &lt;types&gt;
    &lt;type&gt;DELL123&lt;/type&gt;
    &lt;manufacture_id&gt;manu_1&lt;/manufacture_id&gt;
  &lt;/types&gt;
  &lt;types&gt;
    &lt;type&gt;DELL123&lt;/type&gt;
    &lt;manufacture_id&gt;manu_2&lt;/manufacture_id&gt;
  &lt;/types&gt;
  &lt;types&gt;
    &lt;type&gt;HP123&lt;/type&gt;
    &lt;manufacture_id&gt;manu_1&lt;/manufacture_id&gt;
  &lt;/types&gt;
  &lt;types&gt;
    &lt;type&gt;HP123&lt;/type&gt;
    &lt;manufacture_id&gt;manu_2&lt;/manufacture_id&gt;
  &lt;/types&gt;
&lt;/manufactures&gt;

<?xml version="1.0" encoding="ISO-8859-15"?>

</sales>

<types>

<manufacture_id>manu_1</manufacture_id>

</types>

<types>

<manufacture_id>manu_2</manufacture_id>

</types>

<types>

<manufacture_id>manu_1</manufacture_id>

</types>

<types>

<manufacture_id>manu_2</manufacture_id>

</types>

</manufactures>

In the output flow, the root element is changed to manufactures, the sales information is selected and consolidated into
the sale element and the manufacture element is reduced to one single level.

To replicate this scenario, proceed as follows:

Dropping and linking the components

To do this, perform the following operations:

On the workspace, drop tFileInputXML, tXMLMap,
tLogRow and tFileOutputXML from the Palette.
Right-click tFileInputXML to open its
contextual menu and select the Row >
Main link from this menu to connect
this component to the tXMLMap
component.
Repeat this operation to connect tXMLMap
to tLogRow using Row > *New Output*
(Main) link. A dialog box pops up to prompt you to name this
output link. In this scenario, name it as
outDoc.
Do the same to connect tLogRow to
tFileOutputXML using the Row > Main
link.

Configuring the input flow

To do this, do the following:

Double-click tFileInputXML to open its
Basic settings view.
Click the […] button next to Edit schema to open the schema editor.
Click the [+] button to add one row to
the editor and rename it as doc.
In the Type column, select Document from the drop-down list as the type of
the input flow.
In the File name/Stream field, browse to
or type in the path to the XML source that provides the customer
data.
In the Loop XPath query field, type in
"/" to replace the default one. This means the source data
is queried from the root.
In the XPath query column of the
Mapping table, type in the XPath. In
this scenario, type in ".", meaning that all of the data from
source are queried.
In the Get Nodes column of the Mapping table, select the check box.

Configuring tXMLMap with multiple loops

To do this, proceed as follows:

Double-click the tXMLMap component to
open the Map Editor.

Note that the input area is already filled with the default basic XML
structure and that the top table is the main input table.
In the left table, right-click doc to
open the contextual menu.
From this contextual menu, select Import From
File and in the pop-up dialog box, browse to the
corresponding source file in order to import therefrom the XML structure
used by the data to be received by tXMLMap.
In this scenario, the source file is input.xml, which
provides the data read and loaded by tFileInputXML.
In the imported XML tree, right-click the manufacture node and select As loop
element to set it as the loop element. Then do the same to
set the types node and the sale node as loop element, respectively.
On the lower part of this map editor, click the Schema editor tab to display the corresponding view.
On the right side of this view, click the [+] button to add one row to the outDoc table and rename this row as outDoc.
In the Type column of this
outDoc row, select Document as the data type. The corresponding XML root is
added automatically to the top table on the right side which represents the
output flow.
On the right side in the top table labelled outDoc, import the XML data structure that you need to use
from the corresponding XML source file. In this scenario, it is ref.xml. This file provides the expected XML
structure mentioned earlier.
Right-click the manufacture node and
select As loop element from the contextual
menu. Then do the same to set the types
node and the sale node as loop element,
respectively.

Then you can begin to map the input flow to the output flow.
In the top table on the input side (left) of the map editor, click
the @category node and drop it to the
Expression column in the row
corresponding to the output row you need to map. In this scenario, it is the
@category node.
Do the same to map:
- @name to @name
- @unit under the summary node to @unit
- @id to @id and to manufacture id, respectively
- @date to @date
- name to @name
- type to type
- @type to @sales_type
- income to sale (loop)
If required to generate single XML flow, click the wrench icon on top of
the output side to open the setting panel and set the All in one feature as true.
In this example, this option is set as true. For further information about the All in one feature, see Talend Studio
User Guide.
Click the […] button next to the
manufacture loop element to open the
[Configure source loops] dialog box,
and then click the [+] button to add one
source loop manufacture. Do the same to
sale loop element and add one source
loop sale.
Click the […] button next to the
types loop element to open the
[Configure source loops] dialog box.
Then click the [+] button to add two source loops types and manufacture,
and make sure the sequence number of types source loop is 0.
This way, the relative part of the output flow will be sorted with regards
to the values of the type element.

Note

When a loop element receives mappings from more than one loop element
of the input flow, it allows you to set the sequence of the input loops.
For example, in this scenario the types loop element of the output flow is mapped with
@id which belongs to the
manufacture loop element and
type which belongs to the
types loop element. The output
flow will be sorted according to the primary types loop.
Click OK to validate the mappings and
close the Map Editor.

Note

If you close the Map Editor without
having set the required loop elements as described earlier in this
scenario, the root element will be automatically set as loop
element.

Configuring the output flow

To do this, proceed as follows:

Double-click tLogRow to open its
Component view.
If this component does not have the same schema of the preceding
component, a warning icon appears. In this case, click the Sync columns button to retrieve the schema from
the preceding one and once done, the warning icon disappears.
Click OK to validate these changes and
accept the propagation prompted by the pop-up dialog box.
Double-click tFileOutputXML to open its
Component view.
In the File Name field, browse to or
enter the path to the file you need to generate the output flow in.
Select the Incoming record is a document
check box.

Executing the Job

To execute this Job, press F6.

Once done, the Run view is opened automatically,
where you can check the execution result.

Open the file generated, and you will see the expected products data restructured
for manufacturing.

Document get from Talend https://help.talend.com

Thank you for watching.

Docs 5.x

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tXMLMap

tXMLMap properties

Scenario 1: Mapping and transforming XML data

Dropping and linking the components

Note

Configuring the input flow

Note

Configuring tXMLMap for transformation

Note

Note

Note

Configuring tLogRow to display the customer information

Executing the Job

Scenario 2: Launching a lookup in a second XML flow to join complementary data

Configuring the data flow for lookup

Note

Note

Configuring the transformation

Executing the Job

Scenario 3: Mapping data using a filter

Scenario 4: Catching the data rejected by lookup and filter

Note

Configuring the mapping and running the Job

Scenario 5: Mapping data using a group element

Note

Note

Note

Note

Scenario 6: Classing the output data with aggregate element

Note

Note

Note

Scenario 7: Restructuring products data using multiple loop elements

Dropping and linking the components

Configuring the input flow

Configuring tXMLMap with multiple loops

Note

Note

Configuring the output flow

Executing the Job

Scenario 2: Launching a lookup in a second XML flow to join complementary
data