处理大数据对象 -处理BLOB数据

import java.sql.* ;
import java.io.File ;
import java.io.FileInputStream ;
import java.io.InputStream ;
public class BlobDemo01
{   
    //定义数据库驱动程序
    public static final String driver = "org.gjt.mm.mysql.Driver" ;
    //定义数据库连接地址
    public static final String url = "jdbc:mysql://localhost:3306/spiderman" ;
    //定义数据库名称
    public static final String user = "root" ;
    //定义数据库密码
    public static final String pass = "" ;

    public static void main(String[] args)
    {   //加载数据库驱动程序
        try
        {
            Class.forName(driver) ;
        }
        catch(ClassNotFoundException e)//抛出异常
        {
            e.printStackTrace() ;
            return ;
        }

        //加载数据库连接
        Connection conn = null ;
        try
        {
            conn = DriverManager.getConnection(url,user,pass);

        }
        catch(SQLException e)
        {
            e.printStackTrace() ;
            return ;
        }

        //执行数据库操作
        PreparedStatement pst = null ;
        String name = "IronMan";
        String sql =  "Insert Into userblob(user,photo)values(?,?) "; 
        File f = new File("f:"+File.separator+"shabi.jpg") ;    //指定文件路径
        InputStream input = null ;
        try
        {
            input = new FileInputStream(f) ;
        }
        catch (Exception e)
        {
            e.printStackTrace() ;
        }
        try
        {
            pst = conn.prepareStatement(sql);//实例化Statement对象
            pst.setString(1,name) ;     //设置第一个"?"内容
            pst.setBinaryStream(2,input) ;  //设置输入流
            pst.executeUpdate();
        }
        catch(SQLException e)
        {
            e.printStackTrace();
            return ;
        }

        finally
        {   
            if(pst!=null)
            {
                try
                {
                    pst.close();
                }
                catch(SQLException e)
                {
                    e.printStackTrace();
                }
            }

            if(conn!=null)
            {
                try
                {
                    conn.close();
                }
                catch(SQLException e)
                {
                    e.printStackTrace();
                }
            }
        }       
    }
}

import java.sql.* ;
import java.io.File ;
import java.io.FileInputStream ;
import java.io.InputStream ;
import java.Blob ;
import java.sql.ResultSet ;
import java.io.FileOutputStream ;
import java.io.OutputStream ;
public class StatementDemo01
{   
    //定义数据库驱动程序
    public static final String driver = "org.gjt.mm.mysql.Driver" ;
    //定义数据库连接地址
    public static final String url = "jdbc:mysql://localhost:3306/student" ;
    //定义数据库名称
    public static final String user = "root" ;
    //定义数据库密码
    public static final String pass = "" ;

    public static void main(String[] args)throws Exception
    {   //加载数据库驱动程序
        try
        {
            Class.forName(driver) ;
        }
        catch(ClassNotFoundException e)//抛出异常
        {
            e.printStackTrace() ;
            return ;
        }

        //加载数据库连接
        Connection conn = null ;
        try
        {
            conn = DriverManager.getConnection(url,user,pass);

        }
        catch(SQLException e)
        {
            e.printStackTrace() ;
            return ;
        }

        //执行数据库操作
        PreparedStatement pst = null ;
        ResultSet rs = null ;   //保存查询到的内容
        int id = 1 ;
        String sql =  "select user,photo from userblob where id = ? "; 

        try
        {
            pat = conn.prepareStatement(sql);//实例化PreparedStatement对象

        }
        catch(SQLException e)
        {
            e.printStackTrace();
            return ;
        }
        rs = pst.executeQuery();                 //执行查询
        if(rs.next())
        {
            String name = rs.getString(1) ;
            System.out.println("姓名"+name) ;
            Blob b = rs.getBlob(2) ;
            File f = new File("f:"+File.separator+"load.jpg") ;
            OutputStream output = null ;
            out = new OutputStream(f) ;
            out.write(b.getBytes(1,(int)b.length())) ;
            out.close() ;
        }

        finally
        {   
            if(rs!=null)
            {
                try
                {
                    rs.close();
                }
                catch (SQLException e)
                {
                    e.printStackTrace() ;
                }
            }
            if(pst!=null)
            {
                try
                {
                    pst.close();
                }
                catch(SQLException e)
                {
                    e.printStackTrace();
                }
            }

            if(conn!=null)
            {
                try
                {
                    conn.close();
                }
                catch(SQLException e)
                {
                    e.printStackTrace();
                }
            }
        }       
    }
}