map转dto ，大小写 下划线 驼峰自动转换 


public class UserDTO {
    private Long userId;
    private String userName;
    private Boolean active;
    private java.util.Date createTime;
// get setter 
}

Map< String, Object> map = new HashMap< >();
map.put("user_id", 1001L);
map.put("USER_NAME", "张三");
map.put("active", true);
map.put("create_time", new Date());

UserDTO dto = new UserDTO();;
BeanUtil.fillBeanWithMap(map,dto,false);

dto = BeanUtil.toBean(map,UserDTO.class);

dto = new UserDTO();
BeanUtil.copyProperties(map, dto);

// bean转map 
Map< String, Object> map2 = BeanUtil.beanToMap(dto);