You can develop a custom Sling Model Injector when developing models for Adobe Experience Manager. You can inject parameter values into a Sling Model. The parameter values are used by the Model and you can use them in your business logic. This development article walks you through how to write a custom Sling Model injector by using a Sling Model Request Parameter Injector.
The following illustration shows you an HTL component that uses a custom Sling Model Injector.
To create a Sling Model Injector, you use Java APIs located in the org.apache.sling.models.spi.injectorspecific package.
To read this development article, click https://helpx.adobe.com/experience-manager/using/custom_sling_model_injector.html.