title: how to create one logger for 100 class
body: <p>I want to write a logger for my project . log file for single class is 
  Ok . log for  multiple classes seems problem to me .  I do not want to 
  allocate  one logger for one class , 10 logger for 10 class. I want to 
  some other smart way .means i want to one logger for all classs</p>
  
  <p>how to call one  logger for multiple classs</p>