Spring+Servlet returns Json to the Android client and solves the problem of Chinese garbled characters

0 First of all, the configuration of Spring, as well as the configuration of some JavaBeans and Dao is relatively simple, so I won't go into details. Here are some key issues.


1 Spring uses declarative transactions to perform dependency injection of Dao and Service methods and cannot use declarative transactions
     in Servlets. The solution: use programmatic transactions in the Init method of Servlet:

public void init() throws ServletException {
		// Put your code here
		     super.init();   
        
	       ServletContext servletContext = this .getServletContext();   
	                 
	       WebApplicationContext ctx = WebApplicationContextUtils.getWebApplicationContext(servletContext);   
	                 
	       listService = (ListService)ctx.getBean("listService" );   
	}

2 In the doGet method of the servlet:

//ListService is a Service class that mainly includes some operations to query the database, and returns a List
		List<FoodList> foodList=listService.findAll();
		Iterator<FoodList> foodIterator=foodList.iterator();
		
		//The following code generates Json
		JSONObject outList = null;
		try {
			// First the outermost layer is {}, which is to create an object  
		    outList = new JSONObject();   
		    // The value of the key list1 is an object, so we need to create another object  
		    JSONObject inerList = new JSONObject ();  
		    JSONArray ifo = new JSONArray();
		    while(foodIterator.hasNext()){
		    	FoodList food=foodIterator.next();
		    	inerList.put("id", food.getId());
				inerList.put("name", food.getName());
				inerList.put("img", food.getImg());	
				ifo.put (inerList);
		    }
		    outList.put("status",true);
		    outList.put("total",101254);
		    outList.put("tngou", ifo);
			
		} catch (Exception e) {
			// TODO: handle exception
		}
		byte[] b=outList.toString().getBytes("UTF-8");
		response.getOutputStream().write(b);

  In the doGet method the key is

byte[] b=outList.toString().getBytes("UTF-8");
		response.getOutputStream().write(b);

This code, because the database set in mysql is in utf-8 format, it must be set to UTF-8 format here, otherwise the json Chinese is garbled.

3 Parse the json code on the Android client:

URL url = new URL(Url);
		        HttpURLConnection connection = (HttpURLConnection) url
		                .openConnection();
		        connection.setRequestMethod("GET");
		        // Fill in apikey into HTTP header
		        //connection.setRequestProperty("apikey",  "your apikey");
		        connection.connect();
		        InputStream is = connection.getInputStream();
		        reader = new BufferedReader(new InputStreamReader(is, "UTF-8"));
		        String strRead = null;
		        while ((strRead = reader.readLine()) != null) {
		            sbf.append(strRead);
		            sbf.append("\r\n");
		        }
		        reader.close();
		        result = sbf.toString();
		    } catch (Exception e) {
		        e.printStackTrace ();
		    }
		    try {
		    	MeiShi item;
				JSONObject jsonObject=new JSONObject(result);
				JSONArray jsonArray=jsonObject.getJSONArray("tngou");
				for(int i=0;i<jsonArray.length();i++)
				{
					item=new MeiShi();
					jsonObject =jsonArray.getJSONObject(i);					
					item.setName(jsonObject.getString("name"));			
					item.setImg(jsonObject.getString("img"));
					//item.setKeywords(jsonObject.getString("keywords"));
					//item.setCount(jsonObject.getString("count"));
					item.setId(jsonObject.getString("id"));
					resultList.add(item);

Summary: Completed the basic framework of Sring and spring JDBC and Servlet as the server to return data to Json, and solved the problem of parsed json Chinese garbled.