How to retrieve HTTP request header information ?

Methods of HttpServletRequest interface

• getHeader : returns a header value by given header name
  If there are multiple headers with the same name, it returns the first head in the request.
  
• getHeaders : returns all the header values associated with the given header name (Enumeration of Strings)
  
• getHeaderNames : returns names of all the headers
  
• getIntHeader : returns header value (String) into int format
  If it cannot translate the header value to an int, a NumberFormatException is thrown.
  
• getDateHeader : returns header value (String) into Date format
  If it cannot translate the header to a Date object, an IllegalArgumentException is thrown.