1、mysql:/localhost/img?user=root&password=root&useUnicode=true&characterEncoding=gbk;Connection conn = DriverManager.getConnection(url);PreparedStatement pstmt = INSERT INTO myTable(image) VALUES (?)pstmt = conn.prepareStatement(sql);File file = new File(file的URLInputStream imageStream = new FileInput
2、Stream(file);pstmt.setBinaryStream(1, imageStream, (int) file.length();pstmt.executeUpdate();pstmt.close();conn.close();取:PreparedStatement pstmt = conn.prepareStatement(select image from myTable where id=?/设置IDbyte buffer = new byte4096;File file = new File(outfile);/读取后要保存的位置FileOutputStream fos =
3、 new FileOutputStream(file);ResultSet rs = pstmt.executeQuery();InputStream in = rs.getBinaryStream(imageint size = -1;while (size = is.read(buffer) != -1) fos.write(buffer, 0, size);/如果把fos改成是servlet中的response.getOutputStream(),就可以将图片返回给客户端显示了。/关闭资源二、JSP在MySQL中存取图片2008年04月04日 星期五 23:41为了使用JSP灵活,需要把
4、各种文件储存到数据库中,然后需要的时候把它读取出来显示到客户端。这些文件包括音乐,图片,文本等,人们统称为二进制文件。首先,二进制文件储存到数据库的过程:打开文件,将内容读到缓冲区,然后直接联线创建jdbc语句对象,使用该缓冲区的数据,并执行更新,就完成了储存。例子: 首先在mysql中创建一个表 picture_dbcreate table picture_db(file_name varchar(255) not null,content longblob,primary key (file_name);接下来就是用java写储存文件的代码:假设要储存的图片名称是:01.jpg (放在同一
5、个目录下)import java.sql.*;import java.io.*;import java.nio.*;public class UploadImage protected Connection dbConnection;protected String driverName = com.mysql.jdbc.Driverprotected String dbURL = /localhost:3306/sample_dbprotected String userID = rootprotected String passwd = yourpasswordpublic boolean
6、 storeImage(String sqlstr,File file)tryFileInputStream fin = new FileInputStream(file);ByteBuffer nbf = ByteBuffer.allocate(int)file.length();byte array = new byte1024;int offset =0,length=0;while(length=fin.read(array)0)if(length!=1024) nbf.put(array,0,length);else nbf.put(array); offset+=length; f
7、in.close();byte content = nbf.array();return setImage(sqlstr,content);catch(FileNotFoundException e) e.printStackTrace();catch (IOException e)return false;private boolean setImage(String sqlstr,bytein)boolean flag = false;if(sqlstr=null) sqlstr=select * from picture_db Class.forName(driverName); dbC
8、onnection = DriverManager.getConnection(dbURL,userID,passwd);Statement stmt = dbConnection.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE);ResultSet rs = stmt.executeQuery(sqlstr);if(rs.next() rs.updateBytes(2,in); rs.updateRow();else rs.moveToInsertRow(); rs.updateStri
9、ng(1,01 rs.insertRow(); rs.close(); flag=true;catch(Exception e)return flag;public static void main(String args) UploadImage upload = new UploadImage();01.jpgif(upload.storeImage(null, file)System.out.print(tureFalse如果执行成功的话,系统打印“true 否则“false.最后就是将图片度取出来:与储存的过程相反,它是县建立连接,创建数据库查询的jdbc对象,使用该语句来返回二进制结
10、果,保存到文件当中。showImage.jsp% page import=java.sql.*java.io.*com.sun.image.codec.jpeg.*javax.imageio.*java.awt.image.*htmlheadmeta http-equiv=Content-Type content=titleshowDBImage/headbody%String showImage =select * from picture_db where file_name =01Connection conn = null;BufferedInputStream inputImage
11、= null;String driverName = String dbURL = String userID = String passwd = Class.forName(driverName).newInstance(); conn = DriverManager.getConnection(dbURL,userID,passwd); Statement st = conn.createStatement(); ResultSet rs = st.executeQuery(showImage);while(rs.next() Blob blob = (Blob)rs.getBlob(co
12、ntent inputImage = new BufferedInputStream(blob.getBinaryStream(); BufferedImage image = null; image = ImageIO.read(inputImage);ServletOutputStream sos = response.getOutputStream(); JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(sos); encoder.encode(image); inputImage.close();catch(SQLExcept
13、ion e)catch(IOException e)/body/html三、/*-表结构-表名:student2+-+-+-+-+-+-+| Field | Type | Null | Key | Default | Extra | id | int(4) | NO | PRI | NULL | | name | varchar(20) | YES | | NULL | | stupic | blob | YES | | NULL | |*/package com.ibm.jdbc;public class StoreBLOB public static void main(String ar
14、gs) /连接MySQl数据库 Connection con=DBManager.getConnection(); PreparedStatement ps=null; InputStream in=null; try /从本地硬盘读取一张读片 in=new FileInputStream(d:/111.jpg ps=con.prepareStatement(insert into student2 values(?,? ps.setInt(1,2); ps.setString(2, Tom ps.setBinaryStream(3, in, in.available(); ps.execut
15、eUpdate(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); catch (SQLException e) / TODO Auto-generated catch block e.printStackTrace(); finally try /关闭流 if(in!=null) in.close(); catch (IOException e) /关闭相关连接 DBManager.close(ps, con); 取出操作public class GetBLOB public stat
16、ic void main(String args) Connection con=DBManager.getConnection(); Statement st=null; ResultSet rs=null; InputStream in=null; OutputStream out=null; try st=con.createStatement(); rs=st.executeQuery(select stupic from student2 where id=2 rs.next(); /将光标指向第一行 /从rs中读取stupic放进InputStream对象中 in=rs.getBi
17、naryStream(stupic /申明byte数组,用来存放图片流 byte b=new byte40000; in.read(b); /从InputStream对象中读取数据放进byte数组中 /实例化OutputStream对象,在D盘创建一个图片文件 out=new FileOutputStream(/222.jpg /将文件输出,内容则为byte数组里面的数据 out.write(b); out.flush(); catch (SQLException e) / TODO Auto-generated catch block catch (IOException e) finally if(in!=null) in.close(); if(out! out.close(); catch (IOException e) DBManager.close(rs, st, con);/关闭相关连接
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