I'm a newbie on Processing and Arduino. I would like to interface Arduino +SHT75 with Processing to get humidity and temperature data and show it on a GUI. I'm able to easily control the SHT75 sensor with the Arduino IDE and receive data using the Serial Monitor, after the sensor's library have been installed ( link). 

Here is the Arduino code:

2. #include <Sensirion.h>
3.  
4. const uint8_t dataPin =  9;              // SHT serial data
5. const uint8_t sclkPin =  8;              // SHT serial clock
6. const uint8_t ledPin  = 13;              // Arduino built-in LED
7. const uint32_t TRHSTEP   = 5000UL;       // Sensor query period
8. const uint32_t BLINKSTEP =  250UL;       // LED blink period
9.  
10. Sensirion sht = Sensirion(dataPin, sclkPin);
11.  
12. uint16_t rawData;
13. float temperature;
14. float humidity;
15. float dewpoint;
16.  
17. byte ledState = 0;
18. byte measActive = false;
19. byte measType = TEMP;
20.  
21. unsigned long trhMillis = 0;             // Time interval tracking
22. unsigned long blinkMillis = 0;
23.  
24. void setup() {
25.   Serial.begin(9600);
26.   pinMode(ledPin, OUTPUT);
27.   delay(15);                             // Wait >= 11 ms before first cmd
28. // Demonstrate blocking calls
29.   sht.measTemp(&rawData);                // sht.meas(TEMP, &rawData, BLOCK)
30.   temperature = sht.calcTemp(rawData);
31.   sht.measHumi(&rawData);                // sht.meas(HUMI, &rawData, BLOCK)
32.   humidity = sht.calcHumi(rawData, temperature);
33.   dewpoint = sht.calcDewpoint(humidity, temperature);
34.   logData();
35. }
36.  
37. void loop() {
38.   unsigned long curMillis = millis();          // Get current time
39.  
40.   // Rapidly blink LED.  Blocking calls take too long to allow this.
41.   if (curMillis - blinkMillis >= BLINKSTEP) {  // Time to toggle the LED state?
42.     ledState ^= 1;
43.     digitalWrite(ledPin, ledState);
44.     blinkMillis = curMillis;
45.   }
46.  
47.   // Demonstrate non-blocking calls
48.   if (curMillis - trhMillis >= TRHSTEP) {      // Time for new measurements?
49.     measActive = true;
50.     measType = TEMP;
51.     sht.meas(TEMP, &rawData, NONBLOCK);        // Start temp measurement
52.     trhMillis = curMillis;
53.   }
54.   if (measActive && sht.measRdy()) {           // Note: no error checking
55.     if (measType == TEMP) {                    // Process temp or humi?
56.       measType = HUMI;
57.       temperature = sht.calcTemp(rawData);     // Convert raw sensor data
58.       sht.meas(HUMI, &rawData, NONBLOCK);      // Start humidity measurement
59.     } else {
60.       measActive = false;
61.       humidity = sht.calcHumi(rawData, temperature); // Convert raw sensor data
62.       dewpoint = sht.calcDewpoint(humidity, temperature);
63.       logData();
64.     }
65.   }
66. }
67.  
68. void logData() {
69.   Serial.print("Temperature = ");   Serial.print(temperature);
70.   Serial.print(" C, Humidity = ");  Serial.print(humidity);
71.   Serial.print(" %, Dewpoint = ");  Serial.print(dewpoint);
72.   Serial.println(" C");
73. }

Using the Processing with Arduino Library(Firmata) i can easily communicate with other analog (for example LDR) or I2C sensors (simply following the thousand of tutorials available in the Web!), but I don't know how to interface Arduino + SHT75 with Processing IDE. SHT75 sensor has a sort of I2C-like communication protocol.  Here are the datasheet. I've tried with the "serial.Arduino" command ( both "import  processing.serial.*" and "import cc.arduino.*" have been used), but nothing.   Can you help me??? 

Thank you very very much!