code: public static void setter(Object instance, Field field, Object value) {
  		boolean forceAccess = false;
  
  		try {
  			if (!field.isAccessible()) {
  				forceAccess = true;
  				field.setAccessible(true);
  			}
  
  			field.set(instance, value);
  		}
  		catch (IllegalAccessException ex) {
  			throw new ReflectionException(ex);
  		}
  		finally {
  			if (forceAccess) {
  				field.setAccessible(false);
  			}
  		}
  	}
docs: Set value of given field on given instance.
  
  @param instance Instance.
  @param field Field.
  @param value Field value.
  @throws ReflectionException if set operation is not permitted.