package com.itheima.clob.test;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.InputStream;

import java.io.OutputStream;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import org.junit.Test;

import com.itheima.utils.JdbcUtil;

/**

 * 大二进制数据读写(图片，电影，音乐，字节码文件)  Mysq: blob  longblob

 * @author wangli

 *

 *

 use day16;

 create table testblob(

     id int primary key,

     content longblob

 );

 *

 */

public class BlobTest02 {

    //写一个图片到数据表中   测试时显示记录，注意  select id from testblob;

    @Test

    public void testAddBlob(){

        Connection con = null;

        PreparedStatement st =null;

        try {

            con = JdbcUtil.getConnection();

            String sql="insert into testblob values(?,?)";

            st = con.prepareStatement(sql);

            //赋值

            st.setInt(1, 1);

            InputStream is = new FileInputStream("src/1.jpg");//找到src下的文件1.jpg

            st.setBinaryStream(2, is, is.available());

            st.executeUpdate();

        } catch (Exception e) {

            e.printStackTrace();

        }finally{

            JdbcUtil.release(null, st, con);

        }

    }

    @Test  //读取一个图片

    public void testReaderblob(){

        Connection con = null;

        PreparedStatement st =null;

        ResultSet rs = null;

        try {

            con = JdbcUtil.getConnection();

            String sql="select * from testblob where id=?";

            st = con.prepareStatement(sql);

            //赋值

            st.setInt(1, 1);

            //3.读取

            rs = st.executeQuery();

            if(rs.next()){

                //结果集中有数据

                InputStream is = rs.getBinaryStream("content");

                OutputStream os = new FileOutputStream("d:/1.jpg");

                int len=-1;

                byte buffer[] = new byte[1024];

                while((len=is.read(buffer))!=-1){

                    os.write(buffer, 0, len);

                }

                os.close();

                is.close();

            }

        } catch (Exception e) {

            e.printStackTrace();

        }finally{

            JdbcUtil.release(null, st, con);

        }

    }

}