Android中图片的上传和下载代码

File file = new File(imageUrl);   
        String httpUrl = httpDomain+"AddImageServlet"+"?gid="+gid;   
        HttpPost request = new HttpPost(httpUrl);    
        HttpClient httpClient = new DefaultHttpClient();  
        FileEntity entity = new FileEntity(file,"binary/octet-stream");  
        HttpResponse response;  
try {  
            request.setEntity(entity);  
            entity.setContentEncoding("binary/octet-stream");  
            response = httpClient.execute(request);  
              
//如果返回状态为200，获得返回的结果  
 if(response.getStatusLine().getStatusCode()==HttpStatus.SC_OK){    
……//图片上传成功             
}  
}  
catch(Exception e){   
}  

//获得新闻id  
        String gid = request.getParameter("gid");         
        String filePath = getRealPath(request) + "userpic";   
        //      定义上载文件的最大字节   
        int MAX_SIZE = 102400 * 102400;           
        //      声明文件读入类   
        DataInputStream in = null;   
        FileOutputStream fileOut = null;              
        //      取得客户端上传的数据类型   
        String contentType = request.getContentType();                
        if(contentType.indexOf("binary/octet-stream") >= 0){   
            //      读入上传的数据   
            in = new DataInputStream(request.getInputStream());   
            int formDataLength = request.getContentLength();   
            //  如果图片过大  
            if(formDataLength > MAX_SIZE){   
                String errormsg=("上传的文件字节数不可以超过" + MAX_SIZE);  
                out.println(errormsg);  
                return ;  
            }   
        //      保存上传文件的数据   
        byte dataBytes[] = new byte[formDataLength];   
        int byteRead = 0;   
        int totalBytesRead = 0;   
        //      上传的数据保存在byte数组   
        while(totalBytesRead < formDataLength){   
        byteRead = in.read(dataBytes,totalBytesRead,formDataLength);   
        totalBytesRead += byteRead;   
          }   
        String fileName = filePath + gid+".png";  
         //     检查上载文件的目录是否存在   
        File fileDir = new File(filePath);   
        if(!fileDir.exists()){   
        fileDir.mkdirs();   
        }  
        //      创建文件的写出类   
        fileOut = new FileOutputStream(fileName);   
        //      保存文件的数据   
        fileOut.write(dataBytes);   
        fileOut.close();  
          
        //保存文件的路径名  
……    

//获得网络中的图片  
    public Bitmap getGossipImage(String gid){         
        String httpUrl = httpDomain+"userpic/"+gid+".png";        
        Bitmap bitmap = null;            
        HttpGet httpRequest = new HttpGet(httpUrl);    
        //取得HttpClient 对象    
        HttpClient httpclient = new DefaultHttpClient();    
        try {    
            //请求httpClient ，取得HttpRestponse    
            HttpResponse httpResponse = httpclient.execute(httpRequest);    
            if(httpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK){    
                //取得相关信息 取得HttpEntiy    
                HttpEntity httpEntity = httpResponse.getEntity();    
                InputStream is = httpEntity.getContent();                   
                bitmap = BitmapFactory.decodeStream(is);    
                is.close();     
            }else{    
                 Toast.makeText(context,"连接失败!",Toast.LENGTH_SHORT).show();        
            }     
                
        } catch (ClientProtocolException e) {    
            e.printStackTrace();    
        } catch (IOException e) {     
            e.printStackTrace();    
        }      
        return bitmap;  
    }