jsp数据库读取图片

<%@ page import="java.sql.*" %>
<%@ page import="javax.sql.*" %>
<%@ page import="javax.naming.*" %>

<%
    Connection conn = null;
    PreparedStatement pstmt = null;
    ResultSet rs = null;
    byte[] imageBytes = null;

    try {
        Context ctx = new InitialContext();
        DataSource ds = (DataSource) ctx.lookup("jdbc/YourDataSource");
        conn = ds.getConnection();

        String sql = "SELECT image_data FROM images WHERE image_id = ?";
        pstmt = conn.prepareStatement(sql);
        pstmt.setInt(1, Integer.parseInt(request.getParameter("id")));
        rs = pstmt.executeQuery();

        if (rs.next()) {
            imageBytes = rs.getBytes("image_data");
        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (rs != null) rs.close();
        if (pstmt != null) pstmt.close();
        if (conn != null) conn.close();
    }

    if (imageBytes != null) {
        response.setContentType("image/jpeg"); // 根据实际图片类型设置MIME类型
        out.write(imageBytes);
    }
%>