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ADF Utility : Retrieve ApplicationModule object from Managed Bean


Many a times it is required to retrieve the ApplicationModule object from ADF managed beans, for example, to programmatically query a view object.

 Invoke the below class like : AppModuleBean.getService(FacesContext.getCurrentInstance(), APP_MODULE_NAME))

This gives 3 different ways to retrieve the AppModule.
  1. Using BindingContext.
  2. Evaluating DataControl EL expression.
  3. Evaluating Bindings EL expression.
    public class AppModuleBean {

    public static ApplicationModule getService(FacesContext fc, String name) {
       
        DCDataControl dc = fromBindingContext(name);
       
        if(dc == null) {           
            dc = fromEvaluatingDataControlEL(fc, name);
        }
       
        if(dc == null) {
            dc = fromEvaluatingBindingsEL(fc, name);
        }
       
        return (ApplicationModule) dc.getDataProvider();
    }
   
    private static DCDataControl fromBindingContext(String name) {
       
        DCDataControl dc = null;
        BindingContext bindingContext = BindingContext.getCurrent();
        if(bindingContext != null) {
            dc  = bindingContext.findDataControl(name + "DataControl");
        }
        return dc;
    }
   
    private static DCDataControl fromEvaluatingDataControlEL(FacesContext fc, String name) {
       
        DCDataControl dc = null;
        Application app = fc.getApplication();
        ExpressionFactory elFactory = app.getExpressionFactory();
        ELContext elContext = fc.getELContext();
        ValueExpression valueExp = elFactory.createValueExpression(elContext, "#{data." + name + "DataControl}", Object.class);
        dc = (DCDataControl)valueExp.getValue(elContext);
       
        return dc;

    }
   
    private static DCDataControl fromEvaluatingBindingsEL(FacesContext fc, String name) {
       
        DCDataControl dc = null;
        DCBindingContainer bc = (DCBindingContainer)fc.getApplication().evaluateExpressionGet(fc, "#{bindings}", BindingContainer.class);
        if(bc != null) {
            dc = bc.findDataControl(name + "DataControl");
        }
        return dc;
    }
}

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