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Unmapping/remapping pins

See original GitHub issue

If I create an IO config for a pin with

config = DigitalInput.newConfigBuilder(rpi4j).provider("pigpio-digital-input").id("pin-"+pinNumber).address(pinNumber)....
pin = rpi4j.create(config);

the name “pinX” is registered in the Registry and the pin works accordingly.

If I then want to disconnect the pin I call pin.shutdown(rpi4j); which seems to forward the disconnect to pigpio but doesn’t unregister the IO in the Registry.

Any attempt to then create a new config with the same id creates an exception:

com.pi4j.io.exception.IOAlreadyExistsException: IO instance [pin14] already exists in the Pi4J runtime context; unable to create a new instance using this reserved id.
	at com.pi4j.provider.impl.ProviderProxyHandler.invoke(ProviderProxyHandler.java:99)
	at com.sun.proxy.$Proxy2.create(Unknown Source)
	at com.pi4j.context.Context.create(Context.java:309)
	at com.pi4j.internal.IOCreator.create(IOCreator.java:60)
	at com.pi4j.internal.IOCreator.create(IOCreator.java:101)
	at com.pi4j.internal.IOCreator.create(IOCreator.java:189)
        ...

The registry on the autoContext doesn’t seem to have a way to remove things from it (it is a DefaultRegistry not RuntimeRegistry)