create table test_img(  id    integer primary key,  name  varchar2(32),  image blob);

import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import oracle.sql.BLOB;public class Test {    public static void main(String[] args) {        // TODO Auto-generated method stub        PreparedStatement pst = null;        ResultSet rs = null;        Connection conn = ConnectionManager.getConnection();        String sql = "insert into test_img(id,name,image) values(?,?,?)";        try {            pst = conn.prepareStatement(sql);            pst.setInt(1, 1);            pst.setString(2, "test");            pst.setBlob(3, BLOB.empty_lob());  //插入空对象empty_blob()              int ii = pst.executeUpdate();            OutputStream os = null;            String q_sql = "select image from test_img where id = ? for update"; // 锁定数据行进行更新              pst = conn.prepareStatement(q_sql);            pst.setInt(1, 1);            rs = pst.executeQuery();            if (rs.next()) {                oracle.sql.BLOB blob = (oracle.sql.BLOB) rs.getBlob("image");                os = blob.getBinaryOutputStream();                InputStream is = new FileInputStream("D:\\image.jpg");                int i = 0;                while ((i = is.read()) != -1) {                    os.write(i);                }            }            os.flush();            os.close();            ConnectionManager.closeAll(rs, pst, conn); // 关闭资源        } catch (SQLException e) {            e.printStackTrace();        } catch (FileNotFoundException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }    }}

import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class ConnectionManager {    public static final String DRIVER = "oracle.jdbc.driver.OracleDriver";    public static final String URL = "jdbc:oracle:thin:@localhost:1521/orcl";    public static final String USERNAME = "test";    public static final String PASSWORD = "test";    /**     * 通过静态代码块 注册数据库驱动     */    static{        try {            Class.forName(DRIVER);        } catch (ClassNotFoundException e) {            e.printStackTrace();        }    }    /**     * 获得Connection     *      * @return     */    public static Connection getConnection() {        Connection conn = null;        try {            conn = DriverManager.getConnection(URL,USERNAME,PASSWORD);        }catch (SQLException e) {            e.printStackTrace();        }        return conn;    }    /**     * 关闭ResultSet     * @param rs     */    public static void closeResultSet(ResultSet rs) {        if (rs != null) {            try {                rs.close();            } catch (SQLException e) {                e.printStackTrace();            }        }    }    /**     * 关闭Statement     * @param st     */    public static void closeStatement(Statement st) {        if (st != null) {            try {                st.close();            } catch (SQLException e) {                e.printStackTrace();            }        }    }    /**     * 关闭Connection     * @param conn     */    public static void closeConnection(Connection conn) {        if (conn != null) {            try {                conn.close();            } catch (SQLException e) {                e.printStackTrace();            }        }    }    /**     * 关闭全部     * @param rs     * @param sta     * @param conn     */    public static void closeAll(ResultSet rs,Statement sta,Connection conn){        closeConnection(conn);        closeStatement(sta);        closeResultSet(rs);    }}