Android端从服务器抓取的几种常见的数据的处理方式

1、图片

public void look(View v) {    String path = et_path.getText().toString();      try {     URL url = new URL(path);     HttpURLConnection conn = (HttpURLConnection) url.openConnection();          conn.setRequestMethod("GET");     conn.setConnectTimeout(5000);     if(conn.getResponseCode() == 200){      InputStream is = conn.getInputStream();      Bitmap bitmap = BitmapFactory.decodeStream(is);      if(bitmap != null){       iv.setImageBitmap(bitmap);      }     }    } catch (Exception e) {     e.printStackTrace();    }   }

2、网页源码

public void look(View v) {    String path = et_path.getText().toString();      try {     URL url = new URL(path);     HttpURLConnection conn = (HttpURLConnection) url.openConnection();          conn.setRequestMethod("GET");     conn.setConnectTimeout(5000);          if(conn.getResponseCode() == 200){      InputStream is = conn.getInputStream();            ByteArrayOutputStream bos = new ByteArrayOutputStream();      byte[] buffer = new byte[1024];      int len = 0;            //把流转化成文本信息      while((len = is.read(buffer)) != -1){       bos.write(buffer,0,len);      }            String html  = bos.toString();      html_tv.setText(html);            is.close();      bos.close();     }    } catch (Exception e) {     e.printStackTrace();    }   }

3、Xml形式的数据

public List<HeaderNew> getHeaderNews(Context context) throws Exception{        String path = context.getResources().getString(R.string.serverurl);        URL url = new URL(path);    HttpURLConnection conn = (HttpURLConnection) url.openConnection();              conn.setRequestMethod("GET");    conn.setConnectTimeout(5000);        if(conn.getResponseCode() == 200){     InputStream is = conn.getInputStream();     return parserHeaderNews(is);    }        return null;   }     public List<HeaderNew> parserHeaderNews(InputStream is) throws Exception {    List<HeaderNew> headerNews = null;    HeaderNew headerNew = null;        XmlPullParser parser = Xml.newPullParser();           parser.setInput(is,"UTF-8");        int eventType = parser.getEventType();        while(eventType != XmlPullParser.END_DOCUMENT){     switch(eventType){     case XmlPullParser.START_TAG:      if("HeaderNews".equals(parser.getName())){       headerNews = new ArrayList<HeaderNew>();      }else if("HeaderNew".equals(parser.getName())){       headerNew = new HeaderNew();      }else if("image".equals(parser.getName())){       headerNew.setImage(parser.nextText());      }else if("title".equals(parser.getName())){       headerNew.setTitle(parser.nextText());      }else if("content".equals(parser.getName())){       headerNew.setContent(parser.nextText());      }else if("count".equals(parser.getName())){       headerNew.setCount(parser.nextText());      }      break;     case XmlPullParser.END_TAG:      if("HeaderNew".equals(parser.getName())){       headerNews.add(headerNew);       headerNew = null;      }      break;     default:      break;     }          eventType = parser.next();    }        return headerNews;   }

4、抓取JSON格式的数据

抓取JSON格式的数据是以抓取网页源码为基础的。

public List<HeaderNew> getHeaderNewsFromJSON(Context context) throws Exception{    List<HeaderNew> headerNews = new ArrayList<HeaderNew>();        String path = context.getResources().getString(R.string.serverurl_json);        URL url = new URL(path);    HttpURLConnection conn = (HttpURLConnection) url.openConnection();        conn.setRequestMethod("GET");    conn.setConnectTimeout(5000);    if(conn.getResponseCode() == 200){     InputStream is = conn.getInputStream();               ByteArrayOutputStream bos = new ByteArrayOutputStream();     byte[] buffer = new byte[1024];     int len = 0;     while((len = is.read(buffer)) != -1){      bos.write(buffer,0,len);     }     String json = bos.toString();          JSONArray jsonArray = new JSONArray(json);          for(int i = 0 ; i < jsonArray.length() ; ++i){      JSONObject jsonObject = (JSONObject) jsonArray.get(i);      HeaderNew headerNew = new HeaderNew();            headerNew.setImage(jsonObject.getString("image"));      headerNew.setTitle(jsonObject.getString("title"));      headerNew.setContent(jsonObject.getString("content"));      headerNew.setCount(jsonObject.getString("count"));            headerNews.add(headerNew);     }    }        return headerNews;   }

5、抓取Xml形式的数据与抓取JSON形式的数据的区别

构建时的区别：

1）Xml形式的数据

    服务器端直接返回数据集合,由JSP来构建XML形式的数据

代码如下：

 servlet：

public void doGet(HttpServletRequest request, HttpServletResponse response)     throws ServletException, IOException {      HeaderNewsService service = new HeaderNewsService();    List<HeaderNew> headerNews = service.getHeaderNews();        request.setAttribute("headerNews", headerNews);    request.getRequestDispatcher("/WEB-INF/page/headernewsxml1.jsp").forward(request, response);   }

jsp：

<?xml version="1.0" encoding="UTF-8"?>  <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>  <%@ page contentType="text/html; charset=utf-8" %>  <HeaderNews>    <c:forEach items="${headerNews}" var="headerNew">      <HeaderNew>         <image>${headerNew.image }</image>         <title>${headerNew.title }</title>         <content>${headerNew.content}</content>         <count>${headerNew.count}</count>      </HeaderNew>    </c:forEach>  </HeaderNews>

2）JSON形式的数据

在服务器端构造好JSON格式的数据。JSP页面直接显示即可。

代码如下：

public void doGet(HttpServletRequest request, HttpServletResponse response)     throws ServletException, IOException {        HeaderNewsService service = new HeaderNewsService();    List<HeaderNew> headerNews = service.getHeaderNews();    StringBuilder sb = new StringBuilder("[");        for(HeaderNew headerNew : headerNews){     sb.append("{");     sb.append("image:").append("\"").append(headerNew.getImage()).append("\"").append(",");     sb.append("title:").append("\"").append(headerNew.getTitle()).append("\"").append(",");     sb.append("content:").append("\"").append(headerNew.getContent()).append("\"").append(",");     sb.append("count:").append("\"").append(headerNew.getCount()).append("\"");     sb.append("}");     sb.append(",");    }    sb.deleteCharAt(sb.length() - 1);    sb.append("]");        String json = sb.toString();    request.setAttribute("json",json);    request.getRequestDispatcher("/WEB-INF/page/headernewsjson.jsp").forward(request,response);   }

JSP：

<%@ page contentType="text/html; charset=UTF-8" %>  ${json}

附上JSON数据的格式：

[{ a : b , c : d }  , {.....}]