Sensor headphones, part 1

// Connect the distance sensor to this input pin
#define sensorInputPin 0
 
// This stores the state that the headphones were in the last
// time we checked them
boolean lastHeadphonesOn;
 
// Return true if the headphones were just taken off or put back on.
boolean checkHeadphoneState() {
 
  // If the sensor value is really high, it means that nothing
  // is near it, so the headphones must not be on your head.
  int sensorIn = analogRead(sensorInputPin);
  boolean headphonesOn = sensorIn < 800;
 
  // If our results are different from the last time we checked,
  // return true.
  if (headphonesOn != lastHeadphonesOn) {
    lastHeadphonesOn = headphonesOn;
    return true;
  }
 
  // Otherwise, return false.
  lastHeadphonesOn = headphonesOn;
  return false;
}
 
void setup() {
  Serial.begin(9600);
}  
 
void loop() {
  if (checkHeadphoneState()) {
    if (lastHeadphonesOn) {
      // headphones just put on
      Serial.println("headphones on!");
    }
    else {
      // headphones just removed
      Serial.println("headphones off!");
    } 
  }
}

// Tell processing how to use a serial port
import processing.serial.*;
Serial myPort;
 
void setup() {
  // Open up the first available serial port, and set it to 9600 baud
  myPort = new Serial(this, Serial.list()[0], 9600);
}
 
void draw() {
    // Read from the serial port until we get a linefeed
    int lf = 10;
    byte[] inBuffer = new byte[200];
    myPort.readBytesUntil(lf, inBuffer);
 
    // If we actually got some text, check if it contains a message we were
    // waiting for
    if (inBuffer != null) {
      String myString = new String(inBuffer);
      if (myString.contains("headphones on!")) {
        // Hooray! Turn the music on
        println("Headphones on!!!");
        // Run the Banshee music program with the play command specified.
        // If banshee was already running, it starts up the music again.
        try{
          Runtime.getRuntime().exec("banshee --play");
        }
          catch(java.io.IOException e){
          println(e);
        }
      }
      else if (myString.contains("headphones off!")) {
        println("Headphones off!!!");
        // Run the Banshee music program with the pause command specified.
        // If banshee was already running, it just pauses the music.
        try{
          Runtime.getRuntime().exec("banshee --pause");
        }
          catch(java.io.IOException e){
          println(e);
        }
      }
    }
}