code: private static String getColumnNameFromGetter(Method getter,Field f){
  		String columnName = "";
  		Column columnAnno = getter.getAnnotation(Column.class);
  		if(columnAnno != null){
  			//如果是列注解就读取name属性
  			columnName = columnAnno.name();
  		}
  		
  		if(columnName == null || "".equals(columnName)){
  			//如果没有列注解就用命名方式去猜
  			columnName = IdUtils.toUnderscore(f.getName());
  		}
  		return columnName;
  	}
docs: use getter to guess column name, if there is annotation then use annotation value, if not then guess from field name
  @param getter
  @param f
  @return
  @throws NoColumnAnnotationFoundException