The Azure IoT Hub provided different endpoints for manipulate it. These endpoints can be classified as device, service, resource provider, etc(More detail about endpoints of Azure IoT Hub, please refer Azure IoT Hub endpoints).

And Microsoft provide the SDK in different lanuages for Azure IoT hub based on the different endpoints. For example, Microsoft provides C# SDK for Azure IoT Hub for the device and service endpoints named client library(refer here). And Microsoft also provides the C# SDK for the resource provider as Management.
However there is no JAVA SDK for the resource provider for Azure IoT Hub(refer here). You can use the REST in Java for resource provider endpoint of Azure IoT hub. The REST of CRUD Azure IoT Hub, you can refer the links below:
Create Or Update
Delete
Get
In-addition, if you also want Microsoft to provide the Azure IoT resource provider Java SDK, you can vote the feedback from link below:
Azure IoT Hub management SDK for Java