Java LwM2M IoT3 bootstrap example

[mathieu1fb]

What's new

New classes have been added to handle IoT3 bootstrapping with Live Objects using LwM2M:

• IoT3Identity and Lwm2mIoT3Identity (LwM2M instance for server interactions)
• IoT3ServiceEndpoint and Lwm2mIoT3ServiceEndpoint (LwM2M instance for server interactions)
• Lwm2mCallback to be notified of LwM2M events (bootstrap, registration, etc.)

The Lwm2mClient has been updated to handle the new callback and IoT3-specific object models.

A new Lwm2mExample class has been added to demonstrate the LwM2M IoT3 bootstrap sequence.

Close #276

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What to do

After reviewing code changes:

1. Clone the its-client project on your IDE.
2. Ensure that you have Gradle to be able to build the java/iot3 modules (core, mobility and examples).
3. Find the Lwm2mExample class in the examples module, and set appropriate values for the following objects:

    private static final Lwm2mServer EXAMPLE_LWM2M_SERVER = new Lwm2mServer(
            123456,
            5 * 60,
            "U"
    );
    private static final Lwm2mConfig EXAMPLE_LWM2M_BOOTSTRAP_CONFIG = new Lwm2mConfig.Lwm2mBootstrapConfig(
            "your_endpoint_name",
            "your_url",
            "your_psk_id",
            "your_private_key_in_hex",
            EXAMPLE_LWM2M_SERVER,
            true
    );

4. Run the Lwm2mExample.

---

Expected results

1. You're getting a LwM2M bootstrap success! in the console, followed by:
2. The IoT3 Identity :

IoT3Identity:
ID: <an_id>
PSK identity: <a_psk_identity>
PSK secret key: <a_psk_secret_******>

3. Several instances of IoT3 Service Endpoints:

IoT3ServiceEndpoint:
Service name: <service_name>
Payload: <optional>
URI: <service_uri>
Topic root: <optional>
Server public key: <optional>

IoT3ServiceEndpoint:
Service name: <service_name>
Payload: <optional>
URI: <service_uri>
Topic root: <optional>
Server public key: <optional>

...

4. And finally, a LwM2M registration success!.

[fredOG-2A1]

Ok with the last modification.

[fredOG-2A1]

Running the code leads to expected results:
`
LwM2M bootstrap success!
IoT3Identity:
ID: 192...
PSK identity: zqsd....
PSK secret key: [-13, -89, -7...]

IoT3ServiceEndpoint:
Service name: message
Payload: json
URI: mqtts://cor...
Topic root: default/
Server public key: null

IoT3ServiceEndpoint:
Service name: message
Payload: json
URI: mqtt+wss://cor...
Topic root: default/
Server public key: null

IoT3ServiceEndpoint:
Service name: telemetry
Payload: otlp/json
URI: https://core...
Topic root: null
Server public key: null

IoT3ServiceEndpoint:
Service name: api
Payload: jaeger
URI: https://core...
Topic root: null
Server public key: null

LwM2M registration success!
`

[fredOG-2A1]

Approving :-)