从MySQL数据库读取图片和向数据库插入图片

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MySQL数据库中有一个数据类型为Blob类型，此类型为二进制文件类型。下面为从MySQL数据库读取图片和向数据库插入图片的代码，一些的数据库连接和JDBC代码就省去了。

package com.an.jdbc.bean;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import org.junit.Test;

import com.an.jdbc.utils.JDBCUtils;

public class TestBlob {
	//向数据库中插入图片
	@Test
	public void test1() throws Exception{
		String sql = "update beauty set photo = ? where id = ?";
		Connection connection = JDBCUtils.getConnection();
		PreparedStatement ps = connection.prepareStatement(sql);
		FileInputStream fis = new FileInputStream("C:\\Users\\Administrator\\Desktop\\1.jpg");
		
		ps.setBlob(1, fis);
		ps.setInt(2, 2);
		
		int update = ps.executeUpdate();
	
		System.out.println(update>0?"success":"failure");
		
		JDBCUtils.closeConnection(null, ps, connection);
	}
	
	//从数据库中读取一张图片
	@Test
	public void test2() throws Exception{
		
		String sql = "select photo from beauty where id=?";
		Connection connection = JDBCUtils.getConnection();
		PreparedStatement ps = connection.prepareStatement(sql);
		
		ps.setInt(1, 2);
		ResultSet set = ps.executeQuery();
		
		if(set.next()){
			InputStream inputStream = set.getBinaryStream(1);
			FileOutputStream fos = new FileOutputStream("src\\copy.jpg");
			byte[] b = new byte[1024];
			int len = -1;
			while((len=inputStream.read(b))!=-1){
				fos.write(b, 0, len);
			}
			
			fos.close();
			inputStream.close();
		}
		JDBCUtils.closeConnection(null, ps, connection);
	}
}