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Java Open Clients
Accessing ABL ProDataSets : Preparing and passing ProDataSets as ProDataGraph parameters : Passing a ProDataGraph as OUTPUT

Passing a ProDataGraph as OUTPUT

To pass a ProDataGraph as output, you create a ProDataGraphHolder instance to contain the ProDataGraph, and pass the holder as the proxy method parameter that maps to the application service DATASET or DATASET-HANDLE OUTPUT parameter. You do not need to create an initial ProDataGraph object to instantiate the ProDataGraphHolder instance. The Java Open Client interface creates the ProDataGraph required to hold the data returned from the corresponding output ProDataSet on the AppServer.
To return an output ProDataGraph, get the value of the getProDataGraphValue() method invoked on the output ProDataGraphHolder parameter.
The actual value and content of the output ProDataGraph can vary depending on how the ProDataSet is defined by the application service. For example, if the OUTPUT ProDataSet is passed as a DATASET-HANDLE (dynamically), this value can be null. A null value indicates that the DATASET-HANDLE parameter was set to the Unknown value (?) or undefined (defined with no schema and data) by the application service. A dynamic ProDataSet might also be passed without data-relations created for it, and so on.
Once you have the output ProDataGraph, you can access its data, depending on whether you already know the schema of the corresponding ProDataSet.
* Accessing a ProDataGraph with a known schema
* Accessing the ProDataGraph meta data for an unknown schema