大二进制数据的存取

package cn.itcast.jdbc.lob;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import org.junit.Test;

import cn.itcast.util.JdbcUtil;

//大二进制数据的存取
/*
use day15;
create table t2(
    id int primary key,
    content longblob
);
 */
public class BlobDemo {
    @Test
    public void testAdd(){
        Connection conn = null;
        PreparedStatement stmt = null;
        try{
            conn = JdbcUtil.getConnection();
            stmt = conn.prepareStatement("insert into t2 (id,content) values (?,?)");
            stmt.setInt(1, 1);
            
            InputStream in = new FileInputStream("c:/1.jpg");
            stmt.setBinaryStream(2, in, in.available());
            
            int i = stmt.executeUpdate();
            if(i>0)
                System.out.println("插入成功");
            
        }catch(Exception e){
            e.printStackTrace();
        }finally{
            JdbcUtil.release(null, stmt, conn);
        }
    }
    @Test
    public void testRead(){
        Connection conn = null;
        PreparedStatement stmt = null;
        ResultSet rs = null;
        try{
            conn = JdbcUtil.getConnection();
            stmt = conn.prepareStatement("select * from t2 where id=?");
            stmt.setInt(1, 1);
            //大数据要使用流的形式
            //保存到E盘上
            rs = stmt.executeQuery();
            if(rs.next()){
                InputStream in = rs.getBinaryStream("content");
                OutputStream out = new FileOutputStream("e:/1.jpg");
                byte b[] = new byte[1024];
                int len = -1;
                while((len=in.read(b))!=-1){
                    out.write(b, 0, len);
                }
                out.close();
                in.close();
            }
            
        }catch(Exception e){
            e.printStackTrace();
        }finally{
            JdbcUtil.release(null, stmt, conn);
        }
    }
}