Version

    CTL Templates for Joiners

    This transformation template is used in every Joiner and also in Reformat and DataIntersection.

    Here is an example of how the Source tab for defining the transformation in CTL looks.

    Source Tab of the Transform Editor in Joiners

    Figure 58.1. Source Tab of the Transform Editor in Joiners


    Table 58.2. Functions in Joiners, DataIntersection and Reformat

    CTL Template Functions
    boolean init()
    RequiredNo
    DescriptionInitialize the component, setup the environment, global variables.
    InvocationCalled before processing the first record.
    Returns

    true | false (if false, the graph fails)

    integer transform()
    Requiredyes
    Input Parametersnone
    Returns

    Integer numbers. For detailed information, see Return Values of Transformations.

    Invocation

    Called repeatedly for each set of joined or intersected input records (Joiners and DataIntersection) and for each input record (Reformat).

    Description

    Allows you to map input fields to the output fields using a script. If any part of the transform() function for some output record causes fail of the transform() function, and if the user has defined another function (transformOnError()), processing continues in this transformOnError() at the place where transform() failed.

    If transform() fails and the user has not defined any transformOnError(), the whole graph will fail. The transformOnError() function gets the information gathered by transform() that was gotten from previously successfully processed code. Also an error message and stack trace are passed to transformOnError().

    Example
    function integer transform() {
       $out.0.name = $in.0.name;
       $out.0.address = $in.0.city + $in.0.street + $in.0.zip;
       $out.0.country = toUpper($in.0.country);
       return ALL;
    }
    integer transformOnError(string errorMessage, string stackTrace, integer idx)
    Requiredno
    Input Parametersstring errorMessage
    string stackTrace
    Returns

    Integer numbers. For detailed information, see Return Values of Transformations.

    InvocationCalled if transform() throws an exception.
    Description

    It creates output records. If any part of the transform() function for some output record causes fail of the function, and if the user has defined another function (transformOnError()), processing continues in this transformOnError() at the place where transform() failed.

    If transform() fails and the user has not defined any transformOnError(), the whole graph will fail. The transformOnError() function gets the information gathered by transform() that was gotten from previously successfully processed code. Also an error message and stack trace are passed to transformOnError().

    Example
    function integer transformOnError(
                           string errorMessage, 
                           string stackTrace) {
       $in.0.name = $in.0.name;
       $in.0.address = $in.0.city + $in.0.street + $in.0.zip;
       $in.0.country = "country was empty";
       printErr(stackTrace);
       return ALL;
    }
    string getMessage()
    RequiredNo
    DescriptionPrints an error message specified and invoked by user.
    Invocation

    Called in any time specified by the user (called only when transform() returns value less than or equal to -2).

    Returnsstring
    void preExecute()
    RequiredNo
    Input parametersNone
    Returnsvoid
    Description

    May be used to allocate and initialize resources required by the transformation. All resources allocated within this function should be released by the postExecute() function.

    InvocationCalled during each graph run before the transform is executed.
    void postExecute()
    RequiredNo
    Input parametersNone
    Returnsvoid
    Description

    Should be used to free up any resources allocated within the preExecute() function.

    Invocation Called during each graph run after the entire transform was executed.

    [Important]Important
    • Input records or fields and output records or fields

      Both inputs and outputs are accessible within the transform() and transformOnError() functions only.

    • All of the other CTL template functions allow to access neither inputs nor outputs.

    [Warning]Warning

    Remember that if you do not hold these rules, NPE will be thrown.