Not mine, saving for quick access! http://mishranam.blogspot.ca/2012/03/printing-all-request-parameters-from.html

Print all attributes and parameters from servlet

System.out.println("To out-put All the request-attributes received from request - ");

Enumeration enAttr = request.getAttributeNames(); 
while(enAttr.hasMoreElements()){
 String attributeName = (String)enAttr.nextElement();
 System.out.println("Attribute Name - "+attributeName+", Value - "+(request.getAttribute(attributeName)).toString());
}

System.out.println("To out-put All the request parameters received from request - ");

Enumeration enParams = request.getParameterNames(); 
while(enParams.hasMoreElements()){
 String paramName = (String)enParams.nextElement();
 System.out.println("Attribute Name - "+paramName+", Value - "+request.getParameter(paramName));
}