RFR: DIO-23: [I2C] UnavailableDeviceException when Zulu JRE is used

[Alexander Mironenko]

So it is necessary to change return type from boolean to int and make a several return codes:

{
...
if(device == INVALID_DEVICE_REFERENCE) return DEVICE_CLOSED;
if(!lock) return DEVICE_UNAVAILABLE;

return DEVICE_HAS_BEEN_LOCKED;
}

So upper Java code can handle return code properly. 

> On Feb 2, 2017, at 3:00 PM, Sergey Nazarkin <snazarkin at azul.com> wrote:
> 
> Hi,
> 
> if obtained device is invalid, FALSE must not be returned at all since it may confuse user with improper exception (UnavailableDeviceException instead of DeviceClosedException)
> 
> Sergey Nazarkin
> 
> 
> 
> 
>> On 02 Feb 2017, at 13:56, Alexander Mironenko <alexander.mironenko at oracle.com> wrote:
>> 
>> Hi,
>> 
>> Seems strange if we return true even if device_reverence is INVALID_DEVICE_REFERENCE… It is clear that this function does not lock anything, but anyway if obtained device reference is invalid, it could be locked, right?
>> 
>> Regards,
>> Alex
>> 
>>> On Feb 2, 2017, at 1:45 PM, Sergey Nazarkin <snazarkin at azul.com> wrote:
>>> 
>>> Hi 
>>> 
>>> Please review small fix for the issue reproducible on non-Oracle JRE (Azul Zulu Embedded particularly). 
>>> 
>>> Issue:	https://bugs.openjdk.java.net/browse/DIO-23
>>> Webrev: 	http://cr.openjdk.java.net/~snazarki/dio-23/
>>> 
>>> Sergey Nazarkin
>>> 
>>> 
>>> 
>>> 
>