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javabirt

Getting report template parameter types from BIRT Engine API

I'm rendering my BIRT reports through the provided Java engine. I use this library for that:

<dependency>
    <groupId>org.eclipse.birt.runtime</groupId>
    <artifactId>viewservlets</artifactId>
    <version>4.5.0</version>
</dependency>

However, my report parameters are provided through a HTTP request, where I specify the template to be used and the report parameters too. So when I retrieve them from the URL I don't know their types anymore since they're converted to String, so I would like to know the types for the scalar-parameters in the given report template, in order to cast the parameters to their concrete type.

IReportRunnable runnable = engine.openReportDesign(design);
IRunAndRenderTask task = engine.createRunAndRenderTask(runnable);
task.run();

As I'm using this piece of code to render the report from the template, is there some way to retrieve the scalar parameter types either from IReportRunnable or IRunAndRenderTask? Since parameters are declared in the template file and being it a XML file, they would be parseable, but would be good to know if the engine API supports this.

Solution

  • Just found it, it looks like a bit tricky, though. We need to create a parameter definition task over the runnable element:

    IReportRunnable runnable = engine.openReportDesign(design);
IGetParameterDefinitionTask paramTask = engine.createGetParameterDefinitionTask(runnable);

    Then, we access the definition through the parameter name and we can get the type value for the parameter (i.e. "string"):

    paramTask.getParameterDefn("my_parameter_name").getHandle().getElement()
    .getProperty(null, "dataType").toString();