Blob存储读取图片

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Java代码

package com.jdbctest.clobtest;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.*;
import com.jdbctest.Util.JDBCUtil;
public class BlobTest {
public static void main(String args[]){
Connection conn = null;
Statement stmt = null;
PreparedStatement ps = null;
ResultSet rs = null;
//获取数据库对象
conn = JDBCUtil.getConnection();
//表存在则删除它
String sql = "DROP TABLE IF EXISTS blobtest";
try {
stmt = conn.createStatement();
System.out.println(sql);
stmt.executeUpdate(sql);
//创建表
sql = "CREATE TABLE blobtest(" +
"b_id INT NOT NULL AUTO_INCREMENT,"+
"b_title VARCHAR(50),"+
"b_text LongBlob,"+
"PRIMARY KEY(b_id)"+
")";
System.out.println(sql);
stmt.executeUpdate(sql);
System.out.println("创建数据表成功!");
sql="INSERT INTO blobtest(b_title,b_text)VALUES(?,?)";
ps = conn.prepareStatement(sql);
//插入图片
//File file = new File("F:\\image\\yahoo.jpg");
File file = new File("d:\\wuyu\\image\\sea.jpg");
InputStream inputStream = new FileInputStream(file);
//BufferedInputStream bis=new BufferedInputStream(inputStream);
//以前的时候直接使用setBinaryStream就可以保存图片，但
//数据库的字符集换成 gbk后就不能用了，一直提示参数类型不匹配，在网上查了一下，
//直接向数据库中存byte可解决
//ps.setString(1, file.getName());
//ps.setBinaryStream(2,inputStream,file.length());
//ps.executeUpdate();
try {
ps.setString(1, file.getName());
//新建一byte数组
byte[] buf=new byte[inputStream.available()];
//将文件读入到byte[]中
inputStream.read(buf);
ps.setBytes(2, buf);
ps.executeUpdate();
System.out.println("插入成功！");
} catch (IOException e1) {
System.out.println("保存图片到数据库成功！");
e1.printStackTrace();
}
//读取数据
sql = "SELECT b_title,b_text FROM blobtest";
ps = conn.prepareStatement(sql);
rs = ps.executeQuery();
while(rs.next()){
System.out.println("图片名: "+rs.getString("b_title"));
//System.out.println("电影名: "+rs.getString("b_title"));
Blob blob = rs.getBlob("b_text");
File file2 = new File("d:\\wuyu\\sea.jpg");
OutputStream outputStream = new FileOutputStream(file2);
try {
outputStream.write(blob.getBytes(1,(int)blob.length()));
} catch (IOException e) {
e.printStackTrace();
}
//打印出来的为对象
System.out.println("图片内容: "+ blob.getBinaryStream());
}
} catch (SQLException e) {
e.printStackTrace();
} catch (FileNotFoundException e) {
e.printStackTrace();
}finally{
JDBCUtil.close(rs, stmt, conn);
}
}
}