在java中从BLOB读取XML文件

import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.sql.*;

public class ReadXMLFromBLOB {
    public static void main(String[] args) {
        Connection connection = null;
        PreparedStatement statement = null;
        ResultSet resultSet = null;

        try {
            // 1. 连接数据库
            connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydatabase", "username", "password");

            // 2. 执行查询
            String sql = "SELECT xml_data FROM xml_table WHERE id = ?";
            statement = connection.prepareStatement(sql);
            statement.setInt(1, 1); // 设置查询参数
            resultSet = statement.executeQuery();

            if (resultSet.next()) {
                // 3. 获取BLOB数据
                Blob blob = resultSet.getBlob("xml_data");

                // 4. 读取BLOB数据
                InputStream inputStream = blob.getBinaryStream();
                byte[] data = new byte[(int) blob.length()];
                inputStream.read(data);

                // 5. 解析XML文件
                String xmlString = new String(data);
                // 在这里可以使用XML解析库解析xmlString

                System.out.println(xmlString);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            // 关闭连接和资源
            try {
                if (resultSet != null) {
                    resultSet.close();
                }
                if (statement != null) {
                    statement.close();
                }
                if (connection != null) {
                    connection.close();
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}