refactoring existManager
refactoring existManager

Limseunghwan/oss,yona-projects/yona,ihoneymon/yobi,bloodybear/yona,ahb0327/yobi,bloodybear/yona,violetag/demo,Limseunghwan/oss,oolso/yobi,naver/yobi,doortts/fork-yobi,ahb0327/yobi,ChangsungKim/TestRepository01,brainagenet/yobi,yona-projects/yona,doortts/forked-for-history,naver/yobi,doortts/fork-yobi,naver/yobi,yona-projects/yona,yona-projects/yona,doortts/forked-for-history,brainagenet/yobi,ihoneymon/yobi,oolso/yobi,doortts/fork-yobi,bloodybear/yona,brainagenet/yobi,bloodybear/yona,ahb0327/yobi,ChangsungKim/TestRepository01,ihoneymon/yobi,doortts/fork-yobi,violetag/demo,doortts/forked-for-history,Limseunghwan/oss,oolso/yobi