Create expressions
You create expressions in the Mapping window, using a number of methods that differ depending upon the complexity of the source to target transformation.
- Drag and Drop
You use the drag-and-drop feature to create an expression when the data in the source is transferred to the target field exactly as it is, and no transformation is required. - Typing an expression
Using the Mapping window, you can select a class and property on the Source pane and enter a enter an expression in the Target pane that is used to transform the source. - Selecting a deciding class
Sometimes you must map more than one class in a source to a single class in the target. For example, suppose that the target has a single Computer class but the source has multiple classes for Computer, such as Client, BIOS, and RAM. When creating expressions, if you use multiple classes in the source to migrate data into a single class in the target, Integration Composer adds each class in the source to the list of values for the Deciding Class drop-down list in the Target pane. - Setting up multiple cases
You use the case selection feature when you need to migrate data from multiple classes in the source into multiple instances in a single target class. The case selection feature lets you create a set of expressions that apply on a case-by-case basis to the same target class. - Expression Builder
You use the Expression Builder feature to create complex or intricate expressions that are lengthy and time consuming to enter. Expression Builder provides a large text editing area and access to a library of predefined functions and operators that facilitate creation of complex transformation expressions. - Arithmetic operators
- Literals
In an expression, a literal is a value that remains unchanged when Integration Composer creates data in the target; literal values are transferred exactly as written. In Integration Composer, you can specify literals for strings and for the following primitive data types: boolean, char, integer, and floating-point.
Parent topic: Expressions