如何测试一个对象所占的内存的大小，此题目在C中是比较好实现的，但是JAVA就没有提供专门的方法进行测试，你有没有好的建议？-How to test an object the size of share memory, this topic is better in the C implementation, but JAVA is no way to provide specialized testing, do you have any good suggestions?
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001382s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.094446s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001084s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001313s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001868s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003426s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000913s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003581s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.014523s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001007s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 53259 [ RunTime:0.019329s ]
