I've the raspberry pi model b and i am trying to connect a temperature sensor(DHT11). I am facing problem on how to fetch the data from the sensor. I am using JAVA. Which API should i use to get this working? What else should i need to know?
DHT11 is a n analog o/p temp sensor. so its real easy to use. but on the other side it doesn't have a proper datasheet( it has one but its in Chinese). so i will suggest use any temp sensor from TI,AD, Honeywell. i use SHT25 its low cost and it can do temp and humidity. its accuracy is around 1.8% and 0.2'C.
it comes with I2C communication and real easy to use. you can find java,python code here for Pi I2C.
You need a linux driver that you can call from Java and I don't think that there is one for the DHT11. I have used the code in the book Raspberry Pi IoT In C which interfaces directly without any drivers. You could do the same but you would either need to call a C function that read the data or write your own GPIO version in Java using pi4j It is difficult to know if Java is fast enough to do the job.