23.9 데이터 읽기

package ch20.oracle.sec09.exam02;

import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class BoardSelectExample {
	public static void main(String[] args) {
		Connection conn = null;
		try {
			// JDBC Driver 등록
			Class.forName("oracle.jdbc.OracleDriver");

			// 연결하기
			conn = DriverManager.getConnection(
				"jdbc:oracle:thin:@localhost:1521/orcl",
				"java",
				"oracle"
			);

			// 매개변수화된 SQL 문 작성
			String sql = "" +
				"SELECT bno, btitle, bcontent, bwriter, bdate, bfilename, bfiledata " +
				"FROM boards " +
				"WHERE bwriter=?";

			// PreparedStatement 얻기 및 값 지정
			PreparedStatement pstmt = conn.prepareStatement(sql);
			pstmt.setString(1, "winter");

			// SQL 문 실행 후 ResultSet을 통해 데이터 읽기
			ResultSet rs = pstmt.executeQuery();
			while (rs.next()) {
				// 데이터 행을 읽고 Board 객체 생성
				Board board = new Board();
				board.setBno(rs.getInt("bno"));
				board.setBtitle(rs.getString("btitle"));
				board.setBcontent(rs.getString("bcontent"));
				board.setBwriter(rs.getString("bwriter"));
				board.setBdate(rs.getDate("bdate"));
				board.setBfilename(rs.getString("bfilename"));
				board.setBfiledata(rs.getBlob("bfiledata"));

				// 콘솔에 출력
				System.out.println(board);

				// 파일로 저장
				Blob blob = board.getBfiledata();
				if (blob != null) {
					InputStream is = blob.getBinaryStream();
					OutputStream os = new FileOutputStream("C:/Temp/" + board.getBfilename());
					is.transferTo(os);
					os.flush();
					os.close();
					is.close();
				}
			}
			rs.close();

			// PreparedStatement 닫기
			pstmt.close();
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			if (conn != null) {
				try {
					// 연결 끊기
					conn.close();
				} catch (SQLException e) {}
			}
		}
	}
}