第一步建表：
SQL:
create table images_info(
image_id int(10) not null auto_increment primary key,
image_name varchar(255),
image_size int,
image_date datetime,
image_type varchar(10),
image_data longblob,
image_description varchar(255)，
author varchar(100));
修改图片传入最大值：
mySQL安装目录下的my-small.ini文件里面的max_allowed_packet = 1M修改成：
max_allowed_packet = 32M
（参考：在Linux系统中它的配置在mycnf文件中加入max_allowed_packet=32M就行
在命令行配置的方法是：mysqld-nt –console –max_allowed_packet=32M）
第二步编写java代码：
1.插入图片到数据库中代码片段：
private Connection conn = null;
private PreparedStatement pstmt = null;
private static final String sql = “INSERT INTO images_info(image_id,image_name,image_size,image_date,image_type,image_description,author,image_data)VALUES(null,?,?,now(),?,?,?,?)”;
public boolean addPhoto(ImageVo imageVo) {
boolean flag = false;
try{
//将文件转换为流文件
InputStream photoStream = new FileInputStream(imageVo.getImageData());
//获取数据库连接
conn = ConnectionFactory.getConnection();
pstmt = conn.prepareStatement(sql);
pstmt.setString(1, imageVo.getImageName());
pstmt.setInt(2, imageVo.getImageSize());
pstmt.setString(3 , “jpg”);//图片类型
pstmt.setString(4, imageVo.getDescription());
pstmt.setString(5, imageVo.getAuthor());
pstmt.setBinaryStream(6, photoStream, (int)imageVo.getImageData().length());
int row = pstmt.executeUpdate();
if(row == 1){
flag = true;
}
}catch(FileNotFoundException fe){
fe.printStackTrace();
}catch(SQLException e){
e.printStackTrace();
}finally{
if(null != pstmt){
try{pstmt.close();}
catch(SQLException e){
e.printStackTrace();
}
}
if(null != conn){
try{conn.close();}
catch(SQLException e){
e.printStackTrace();
}
}
}
return flag;
}
2.从数据库读取图片信息
private Connection conn = null;
private PreparedStatement pstmt = null;
private ResultSet rs = null;
//查询具体图片数据流格式
private static final String data_sql = “select image_data from images_info where image_id = ?”;
public void ReadImage(int imageId,String imageName){
FileOutputStream fos = null;
InputStream in = null;
byte[] Buffer = new byte[4096];
try{
conn = ConnectionFactory.getConnection();
pstmt = conn.prepareStatement(data_sql);
pstmt.setInt(1, imageId);
rs = pstmt.executeQuery();
rs.next();
File file = new File(imageName);
if(!file.exists()){
file.createNewFile();//如果文件不存在，则创建
}
fos = new FileOutputStream(file);
in = rs.getBinaryStream(“image_data”);
int size = 0;
while ((size = in.read(Buffer)) != -1) {
fos.write(Buffer, 0, size);
}
}catch(SQLException e){
e.printStackTrace();
}catch(IOException ioe){
ioe.printStackTrace();
}finally{
//关闭数据流
if(null != rs){
try{
rs.close();
}catch(SQLException e){
e.printStackTrace();
}
}
if(null != pstmt){
try{
pstmt.close();
}catch(SQLException e){
e.printStackTrace();
}
}
if(null != conn){
try{
conn.close();
}catch(SQLException e){
e.printStackTrace();
}
}
}
}
对象类属性：
String imageId;
String imageName;
int imageSize;
Date imageDate;
String imageType;
String description;
String author;
File imageData;