http示例代码

//下载文件
 public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        response.addHeader("content-disposition", "attachment;filename=3.jpg");
        
        InputStream in=this.getServletContext().getResourceAsStream("/hadoop.jpg");
        int len=0;
        byte buffer[]=new byte[1024];
        OutputStream out=response.getOutputStream();
        while((len=in.read(buffer))>0){
            out.write(buffer,0,len);            
        }
    }

    //定时刷新
    private void test4(HttpServletResponse response) throws IOException {
        response.setHeader("refresh", "2");
        String data="aaaa123rws";
        response.getOutputStream().write(data.getBytes());
    }

    //通过content-type头，通知浏览器以何种方式解析文件
    public void test3(HttpServletResponse response) throws IOException {
        response.addHeader("content-type", "image/jpeg");
        InputStream in=this.getServletContext().getResourceAsStream("/hadoop.jpg");
        int len=0;
        byte buffer[]=new byte[1024];
        OutputStream out=response.getOutputStream();
        while((len=in.read(buffer))>0){
            out.write(buffer,0,len);            
        }
    }
    
    //数据压缩
    public void test2(HttpServletResponse response) throws IOException {
        String data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
        System.out.println("原始数据大小："+data.getBytes().length);
        ByteArrayOutputStream bout = new ByteArrayOutputStream();
        GZIPOutputStream gout = new GZIPOutputStream(bout);
        gout.write(data.getBytes());
        gout.close();

        byte gzis[] = bout.toByteArray();// 得到压缩后的数据
        System.out.println("压缩后大小："+gzis.length);
        response.setHeader("content-Encoding", "gzip");
        response.setHeader("Content-Length", gzis.length+"");
        response.getOutputStream().write(gzis);
    }

    public void test1(HttpServletResponse response) {
        response.setStatus(302);
        response.addHeader("location", "http://www.baidu.com");
    }