인프런 커뮤니티 질문&답변

학습하는 분들께 도움이 되고, 더 좋은 답변을 드릴 수 있도록 질문전에 다음을 꼭 확인해주세요.

1. 강의 내용과 관련된 질문을 남겨주세요.
2. 인프런의 질문 게시판과 자주 하는 질문(링크)을 먼저 확인해주세요.
(자주 하는 질문 링크: https://bit.ly/3fX6ygx)
3. 질문 잘하기 메뉴얼(링크)을 먼저 읽어주세요.
(질문 잘하기 메뉴얼 링크: https://bit.ly/2UfeqCG)

질문 시에는 위 내용은 삭제하고 다음 내용을 남겨주세요.
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[질문 템플릿]
1. 강의 내용과 관련된 질문인가요? (예/아니오)
2. 인프런의 질문 게시판과 자주 하는 질문에 없는 내용인가요? (예/아니오)
3. 질문 잘하기 메뉴얼을 읽어보셨나요? (예/아니오)

[질문 내용]
.중간에 conn 부분이랑 맨아래 throws SQLException 쪽에 빨간줄이 그어 있긴하는데 같은 코드인것 같은데 어디서 잘못된건지 잘 모르겠습니다. 제가 작성한 코드는

public class JdbcMemberRepository implements MemberRepository{

    private final DataSource dataSource;

    public JdbcMemberRepository(DataSource dataSource){
        this.dataSource = dataSource;
    }
    @Override
    public Member save(Member member) {
        String sql = "insert into member(name) values(?)";

        Connection conn = null;
        PreparedStatement pstmt = null;
        ResultSet rs = null;

        try{
            conn = getConnection();
            pstmt = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);
            pstmt.setString(1, member.getName());
            pstmt.executeUpdate();
            rs = pstmt.getGeneratedKeys();

            if (rs.next()) {
                member.setId(rs.getLong(1));
            } else {
                throw new SQLException("id 조회 실패");
            }
            return member;
        } catch (Exception e) {
            throw new IllegalStateException(e);
        } finally {
            close(conn, pstmt, rs);
        }


    }
    
    @Override
    public Optional<Member> findById(Long id) {
        String sql = "select * from member where id = ?";
        Connection conn = null;
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        try {
            conn = getConnection();
            pstmt = conn.prepareStatement(sql);
            pstmt.setLong(1, id);
            rs = pstmt.executeQuery();
            if(rs.next()) {
                Member member = new Member();
                member.setId(rs.getLong("id"));
                member.setName(rs.getString("name"));
                return Optional.of(member);
            } else {
                return Optional.empty();
            }
        } catch (Exception e) {
            throw new IllegalStateException(e);
        } finally {
            close(conn, pstmt, rs);
        }
    }
    @Override
    public Optional<Member> findByName(String name) {
        String sql = "select * from member where name = ?";
        Connection conn = null;
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        try {
            conn = getConnection();
            pstmt = conn.prepareStatement(sql);
            pstmt.setString(1, name);
            rs = pstmt.executeQuery();
            if(rs.next()) {
                Member member = new Member();
                member.setId(rs.getLong("id"));
                member.setName(rs.getString("name"));
                return Optional.of(member);
            }
            return Optional.empty();
        } catch (Exception e) {
            throw new IllegalStateException(e);
        } finally {
            close(conn, pstmt, rs);
        }
    }
    private Connection getConnection() {
        return DataSourceUtils.getConnection(dataSource);
    }
    private void close(Connection conn, PreparedStatement pstmt, ResultSet rs)
    {
        try {
            if (rs != null) {
                rs.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        try {
            if (pstmt != null) {
                pstmt.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        try {
            if (conn != null) {
                close(conn);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    @Override
    public List<Member> findAll() {
        String sql = "select * from member";
        Connection conn = null;
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        try {
            conn = getConnection();
            pstmt = conn.prepareStatement(sql);
            rs = pstmt.executeQuery();
            List<Member> members = new ArrayList<>();
            while(rs.next()) {
                Member member = new Member();
                member.setId(rs.getLong("id"));
                member.setName(rs.getString("name"));
                members.add(member);
            }
            return members;
        } catch (Exception e) {
            throw new IllegalStateException(e);
        } finally {
            close(conn, pstmt, rs);
        }
        private void close(Connection conn) throws SQLException {
            DataSourceUtils.releaseConnection(conn, dataSource);
    }
}