When creating a Job, Talend Studio enables you to insert a component in the middle of a Row > Main, Row > Reject or Row > Combine connection.
To do so, do the following:
In the Integration perspective, drop two combine and two file components from the Palette onto the design workspace.
Connect the component pairs using a Row > Main (or a Row > Reject) connection and a Row > Combine one.
Drop the component you want to insert in the middle of the row. The link gets bold and then a dialog box displays, prompting you to type in a name for the output link.
Type in a name and click OK to close the dialog box.
You may be asked to retrieve the schema of the target component. In that case, click OK to accept or click No to deny.
The component is inserted in the middle of the link, which is now divided in two links.