code: static Class<?> getSetterType(Method setter) {
  		Class<?>[] parameterTypes = setter.getParameterTypes();
  		if (parameterTypes.length != 1) {
  			throw new BeanUtilsException(
  					String.format("Method %s has %d parameters and cannot be a setter", setter.getName(), parameterTypes.length));
  		}
  
  		return parameterTypes[0];
  	}
docs: Get property type by a setter method.
  @param setter setter of Java bean class
  @return type of the specified setter method
  @throws org.javasimon.utils.bean.BeanUtilsException if specified method does not has setter signature