Data-Flow Editor 

Use

You use the data-flow editor (at the bottom of the mapping editor) to describe the flow of data from one or more source fields to one target field. Since this mapping is only a part of the actual message mapping and refers to a particular target field, this type of mapping is known as a Target Field Mapping.

Features

The data-flow editor comprises the following:

·        An editor window in which you can insert functions and source and target fields as rectangles, and move them as required. These rectangles are known as data-flow objects because you use them to describe the data-flow between source fields and target fields.

·        A function chooser in the lower screen area of the data-flow editor that contains the functions of various function categories. Using this function chooser, you can drag functions as new data-flow objects and drop them in the editor window. Furthermore, by clicking on an empty space in the data-flow editor you can call a function menu to access frequently used functions.

On the left-hand side of the editor window there are general functions that are useful when editing a target field mapping:

General Functions of the Data-Flow Editor

Function	Meaning
Delete Floating Objects	Deletes all data-flow objects that are not connected to a source and target field. Floating data-flow objects are displayed in orange.
Lay Out Mapping	Produces an ordered representation of the target field mapping. You can also call this function by selecting the right mouse button on an empty area of the data-flow editor and moving the mouse quickly back and forth.
Delete Current Mapping	Deletes the target field mapping currently displayed.

Functions of the Context Menu

Function	Use
General functions (see above)	You can also access the general functions explained in the table above by calling the context menu in empty areas of the data-flow editor.
Delete	Deletes one or more data-flow objects (to select multiple objects with the mouse, hold down the CTRL key).
Copy and Insert	Copy from one or more data-flow objects (also to other target field mappings) to reuse the whole or part of the target field mapping. The function copies the data-flow object for which the context menu was called, and the entire ‘object tree’ that determines the input values for the data-flow object. The target field cannot be copied.
Display Queue	Displays the queue for a field or a function for complete target field mappings, if an XML instance has been loaded or entered on the Test tab page. The result queue is displayed for functions, while the results values are displayed for target fields before they are written to the target structure. The target structure specifies which values are taken from this queue, for example, depending on the occurrence value specified in the target structure. You can display multiple queues in parallel in separate windows. Within a queue window, you can update the queue, and number the entries of the queue consecutively.
Context	Sets the context for source fields. In the default setting, each field is in the context of the next higher-level field. If this default setting was overwritten by the menu, the data-flow editor displays the field names in the data-flow object in italics. For more information, see Structure Mapping by Setting the Context.
Find Field	Searches for and selects a field in the structure overview.
Copy Path	Copies the access path for a field to the clipboard to reuse it in another location (insert it using CTRL+V).
Where-Used List	You can call this function from the context menu for the function chooser. The menu shows whether the function is used, and if so, where.

Activities

...

       1.      Once you have selected the source fields and the target field you want (see: Assigning a Field), select a function category from the function chooser:

¡        If you have already created a user-defined function, it is located in the User-Defined function category.

¡        All other categories contain the most important standard functions for message mappings.

       2.      Select a function from the function chooser either by double-clicking, or by using drag and drop to drag it to the editor area.

       3.      Connect the selected function to the other data-flow objects for the source fields and the target field by connecting the small rectangles for the input and output values using drag and drop. However, if you use the secondary mouse button, you do not actually have to connect to the box; instead you can let this connection be created for you within the data-flow object. Arrows represent connected elements.

       4.      To undo a connection, remove the arrow from the corresponding rectangle and drop it anywhere outside the data-flow object.

       5.      To delete any data-flow objects that you no longer require, choose Delete in the context menu. To delete all floating data-flow objects (displayed in light-blue), choose Delete Floating Objects.

       6.      Once all data-flow objects are green the mapping for the target field mapping is complete from a logical point of view.

Example

In the example above, a mapping to the target field name was selected that is connected to the source fields firstName and lastName using the standard function concat. Input values of any data-flow objects are displayed in small rectangles on the left of the object, while output values are displayed on the right of the object. You use these small rectangles to connect data-flow objects to each other so as to define a data flow between multiple source fields and exactly one target field. Technically speaking, a target field mapping is complete once at least one source field has been assigned to a target field and all arguments for each connecting function have values. Since this is the case in the example illustrated here, the data-flow editor displays the connected objects in green.