jdbc blob操作

JdbcUtil

public final class JdbcUtil {

	private static String url = "jdbc:mysql://localhost:3306/blobtest";
	private static String user = "root";
	private static String password = "root";

	private JdbcUtil() {

	}

	static {
		try {
			Class.forName("com.mysql.jdbc.Driver");
		} catch (Exception e) {
			throw new ExceptionInInitializerError(e);
		}
	}

	public static Connection getConnection() throws SQLException {
		return DriverManager.getConnection(url, user, password);
	}

	public static void free(ResultSet rs, Statement stmt, Connection conn) {
		try {
			if (rs != null) {
				rs.close();
			}
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			try {
				if (stmt != null) {
					stmt.close();
				}
			} catch (SQLException e) {
				e.printStackTrace();
			} finally {
				if (conn != null) {
					try {
						conn.close();
					} catch (SQLException e) {
						e.printStackTrace();
					}
				}
			}
		}
	}
}

 

BlobTest

public class BlobTest {

	public static void main(String[] args) throws Exception {
		BlobTest.create();
	}
	
	static void read() throws Exception {
		Connection conn = null;
		Statement st = null;
		ResultSet rs = null;
		try {
			conn = JdbcUtil.getConnection();
			st = conn.createStatement();
			rs = st.executeQuery("SELECT big_bit FROM blob_test");
			while (rs.next()) {
				InputStream in = rs.getBinaryStream("big_bit");
				File file = new File("IMG_0002_bak.jpg");
				OutputStream out = new BufferedOutputStream(
						new FileOutputStream(file));
				byte[] buff = new byte[1024];
				for (int i = 0; (i = in.read(buff)) > 0;) {
					out.write(buff, 0, i);
				}
				out.close();
				in.close();
			}
		} finally {
			JdbcUtil.free(rs, st, conn);
		}
	}

	static void create() throws Exception {
		Connection conn = null;
		PreparedStatement ps = null;
		try {
			conn = JdbcUtil.getConnection();
			String sql = "INSERT INTO blob_table(pic) VALUES (?) ";
			ps = conn.prepareStatement(sql);
			File file = new File("image.jpg");
			InputStream in = new BufferedInputStream(new FileInputStream(file));
			ps.setBinaryStream(1, in, (int) file.length());
			ps.executeUpdate();
			in.close();
		} finally {
			JdbcUtil.free(null, ps, conn);
		}
	}
}