package cn.my.demo1;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.sql.rowset.serial.SerialBlob;

import org.apache.commons.io.IOUtils;
import org.junit.Test;


import cn.jdbc.JdbcUtils;
/**
 * 處理大資料到資料庫裡
 * MP3檔案的存取與讀出
 * 使用Blob類
 * @author Administrator
 *
 */
public class DemoA {
	/**
	 * 儲存MP3檔案
	 * @throws SQLException 
	 * @throws IOException 
	 * @throws ClassNotFoundException 
	 */
	@Test
	public void  fun1() throws ClassNotFoundException, IOException, SQLException {
		Connection con=JdbcUtils.getConnection();
		String sql="insert into table_bin values(?,?,?)";
		PreparedStatement pSt=con.prepareStatement(sql);
		//設定sql的引數
		pSt.setInt(1, 2);
		pSt.setString(2, "認真的雪.mp3");
		/*把檔案變成位元組陣列
		 * Blob物件的獲取通過位元組陣列
		 * 
		 */
		byte[] bytes=IOUtils.toByteArray(new FileInputStream("D:/認真的雪.mp3"));
		Blob blob=new SerialBlob(bytes);
		pSt.setBlob(3, blob);
		pSt.executeUpdate();
	}
	/**
	 * 提取MP3
	 * @throws SQLException 
	 * @throws IOException 
	 * @throws ClassNotFoundException 
	 * 
	 */
	@Test
	public void fun2() throws ClassNotFoundException, IOException, SQLException {
		Connection con=JdbcUtils.getConnection();
		String sql="select * from table_bin";
		PreparedStatement pSt=con.prepareStatement(sql);
		//執行查詢
		ResultSet rs=pSt.executeQuery();
		if(rs.next()){
			/*
			 *把Blob變成磁碟檔案
			 *通過Blob得到輸入流物件
			 *自己建立輸出流物件
			 *把輸入流資料寫入輸入流
			 */
			Blob blob=rs.getBlob("DATA");
			InputStream input=blob.getBinaryStream();
			OutputStream output=new FileOutputStream("D:/ss.mp3");
			//IOUtil是封裝檔案的操作的io流
			IOUtils.copy(input, output);
		}
		
	}
}