@Before
  public void init() throws DataDuplicatedException, DataNotFoundException {
    this.memberService = new MemberServiceImpl();
    memberService.registerMember(testMember1);
    memberService.registerMember(testMember2);

    this.blogService = new BlogServiceImpl();
    blogService.createBlog(testMember1, "first_blog");
    blogService.createBlog(testMember2, "second_blog");
    blogService.createBlog(testMember1, "third_blog");
  }
 @After
 public void end() throws DataNotFoundException {
   blogService.removeBlog(testMember1);
   blogService.removeBlog(testMember2);
   memberService.removeMember(testMember1);
   memberService.removeMember(testMember2);
 }