上传文件到Mysql数据库

First, you need a table in database. Below is the table script:

CREATE TABLE `image` (                   
          `Id` int(11) NOT NULL auto_increment,  
          `Image` blob,                          
          PRIMARY KEY  (`Id`)                    
) ENGINE=InnoDB DEFAULT CHARSET=latin1  

Second,you need a jsp. Below is the HTML block in jsp file:

<form action="TestUploadImageToDB" method="post" enctype="multipart/form-data">
   <input type="file" name="file">
   <input type="submit" value="submit">
</form>

Third, you need a servlet to deal with the file upload. Below is the configuration in web.xml and code:

<servlet>
    <servlet-name>TestUploadImageToDB</servlet-name>
    <servlet-class>com.TestUploadImageToDB</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>TestUploadImageToDB</servlet-name>
    <url-pattern>/TestUploadImageToDB</url-pattern>
  </servlet-mapping>

public class TestUploadImageToDB extends HttpServlet {

	private static final long serialVersionUID = 6397853149875034008L;

	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		boolean isMultipart = ServletFileUpload.isMultipartContent(request);
		if (isMultipart) {
			DiskFileItemFactory factory = new DiskFileItemFactory();
			factory.setSizeThreshold(1024*1024); 
			factory.setRepository(new File("c:\\temp")); 
			ServletFileUpload upload = new ServletFileUpload(factory);
			upload.setSizeMax(100 * 1024 * 1024);
			List items = new ArrayList();
			try {
				items = upload.parseRequest(request);
			} catch (FileUploadException e) {
				e.printStackTrace();
			}
			Iterator iter = items.iterator();
			while (iter.hasNext()) {
				FileItem item = (FileItem) iter.next();
				if (item.isFormField()) {
					String name = item.getFieldName();
					String value = item.getString();
					System.out.println(name + ":" + value);
				} else {
					writeToDB(item.getInputStream());
				}
			}
		}
		response.setContentType("text/html");
		PrintWriter out = response.getWriter();
		out.println("success!");
		out.flush();
		out.close();
	}
	public void writeToDB(InputStream ism){
		Connection con = null;
		try {
			Class.forName("com.mysql.jdbc.Driver").newInstance();
			String URL = "jdbc:mysql://localhost:3306/test?user=root&password=root";
			con = DriverManager.getConnection(URL);
			
			PreparedStatement st = null;
			InputStream in = new BufferedInputStream(ism);
			String sql = "insert into image(Image) values(?)";
			st = con.prepareStatement(sql);
			st.setBinaryStream(1, in);
			int i = st.executeUpdate();
			System.out.println("==>" + i);
			in.close();
			
		}catch(Exception e){
			e.printStackTrace();
		} finally {
			try {
				con.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
}