限制上传大小、用COS实现文件上传与下载 五（63）

package cn.hx;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.UUID;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.oreilly.servlet.MultipartRequest;
import com.oreilly.servlet.multipart.DefaultFileRenamePolicy;
import com.oreilly.servlet.multipart.FileRenamePolicy;
/**
 * 在Cos中就一个类，
 * MultipartRequest它是request的包装类。
 */
public class CosServlet extends HttpServlet {
 public void doPost(HttpServletRequest request, HttpServletResponse resp)
throws ServletException, IOException {

       //第一步：声明文件的保存目录

       String path = getServletContext().getRealPath("/up");

       //第二步：文件传

       //声明文件重新取名的策略

       FileRenamePolicy rename = new DefaultFileRenamePolicy();

       MultipartRequest req =

              new MultipartRequest(request,path,1024*1024*100,"UTF-8",new MyRename());

//     //第三步：显示信息，

       resp.setContentType("text/html;charset=UTf-8");

       PrintWriter out = resp.getWriter();

       out.print("文件名称1:"+req.getOriginalFileName("img1"));

       out.print("<br/>新名称:"+req.getFilesystemName("img1"));

       out.print("<br/>类型1:"+req.getContentType("img1"));

       out.print("<br/>大小1："+req.getFile("img1").length());

       out.print("<br/>说明:"+req.getParameter("desc1"));

       if(req.getContentType("img1").contains("image/")){

           out.print("<img src=‘"+request.getContextPath()+"/up/"+req.getFilesystemName("img1")+"‘></img>");

       }

    }

}

class MyRename implements FileRenamePolicy{

    public File rename(File file) {

       String fileName = file.getName();

       String extName = fileName.substring(fileName.lastIndexOf("."));

       String uuid = UUID.randomUUID().toString().replace("-","");

       String newName = uuid+extName;//abc.jpg

       file = new File(file.getParent(),newName);

       return file;

    }

}