Ciao,
codice:
FileReader reader = new FileReader("nome file di input");
BufferedReader in = new BufferedReader(reader);
String linea;
while((linea =  in.readline()) != null)
{
   char[] tmp = linea.toCharArray(); 
   if(tmp[0] == "I" && tmp[1] == "D")
  {
     String infox, infoy, infoValues;
     infox = in.readline();
     infoy = in.readline();
     infovalues = in.readline();
     /*
     gestisci qui i valori letti
    */
  }
}