以流的方式输出图片和视频

java

package com.yunfengtech.solution;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;

import com.yunfengtech.solution.util.PropertyUtils;

@WebServlet("/ivs")
public class ImgAndVideoServlet extends HttpServlet {
    
    private static final long serialVersionUID = 1L;
    private static Logger logger = Logger.getLogger("default");
    private static final String JPG = "image/jpeg;charset=GB2312";  
    private static final String PNG = "image/png;charset=GB2312";  
    private static final String MP4 = "video/mpeg4;charset=utf-8";
    
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ImgAndVideoServlet() {
        super();
    }

    ServletContext sc;

    public void init(ServletConfig config) throws ServletException {
        super.init(config);
        sc = config.getServletContext();
    }

    protected void doGet(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }

    protected void doPost(HttpServletRequest request,HttpServletResponse response)  {
        OutputStream output = null;
        InputStream imageIn = null;
        FileInputStream fis = null;
        BufferedInputStream bis = null;
        BufferedOutputStream bos = null;
        try {
            output = response.getOutputStream();// 得到输出流  
            String ft = request.getParameter("ft");
            String fileDir = "";
            String fileName = request.getParameter("fn") ;//URLDecoder.decode(request.getParameter("fn"),"UTF-8");
            fileName = new String(fileName.getBytes("iso-8859-1"),"utf-8");
            response.reset();
            
            if(ft != null && ft.equals("mp4")){
                fileDir = PropertyUtils.getProperty("videoPath");
                
                response.setContentType(MP4);// 设定输出的类型  
                response.setHeader("Content-Disposition", "attachment;filename="  + fileName);  
                File file = new File(fileDir + fileName);    
                int len = (int) file.length();
                byte[] buf = new byte[4096];    
                fis = new FileInputStream(file);    
                len = fis.read(buf);    
                while (len != -1) {    
                    output.write(buf, 0, len);
                    len = fis.read(buf);   
                }   
                output.flush();
            }else if(fileName.toLowerCase().endsWith(".jpg") || fileName.toLowerCase().endsWith(".png")){
                if(fileName.toLowerCase().endsWith(".jpg") ){
                    response.setContentType(JPG);// 设定输出的类型  
                }else{
                    response.setContentType(PNG);// 设定输出的类型  
                }
                
                fileDir = PropertyUtils.getProperty("imagePath");
                imageIn = new FileInputStream(fileDir + fileName);//文件流
                bis = new BufferedInputStream(imageIn);//输入缓冲流
                bos = new BufferedOutputStream(output);//输出缓冲流
                byte data[] = new byte[4096];//缓冲字节数
                int size = 0; 
                size = bis.read(data);
                while (size != -1){
                   bos.write(data,0,size);
                   size = bis.read(data);
                }
                bos.flush();//清空输出缓冲流
            }
            
        } catch (IOException e) {
            logger.error("获取文件流出错："+e);
            e.printStackTrace();
        } finally{
            if(output != null){
                try {
                    output.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }  
            }
            if(imageIn != null){
                try {
                    imageIn.close();// 关闭文件流  
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(fis != null){
                try {
                    fis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(bis != null){
                try {
                    bis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(bos != null){
                try {
                    bos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        
    }
}

servlet

    <servlet>
        <servlet-name>ImgAndVideoServlet</servlet-name>
        <servlet-class>com.yunfengtech.solution.ImgAndVideoServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>ImgAndVideoServlet</servlet-name>
        <url-pattern>/ivs</url-pattern>
    </servlet-mapping>

js

setImage : function(obj, val){
        var imageUrl = "/np/ivs?fn=" + val;
        $(obj).parent().find("div[data-type='image']").html("<img src="+imageUrl+" style= 'width:40px; hight:40px;'/>");
    }