Parsing of json array

For a long time, I often encounter json data from the front end or the data I often crawl from the website, there will be json data, so if you want to get json data, you need to parse the json data

Below I use java language to parse json data

A package needs to be introduced before parsing the data

 

You can download the corresponding jar package from http://mvnrepository.com/artifact/edu.uci.ics here

public class JsonToObject {
	/**Parse the case where the outermost part of the json string is []
	 * [{"rating":["9.6","50"],"rank":1},{"rating":["9.6","50"],"rank":2}]
	 * @throws Exception
	 */
	public List<Map<String, String>> toMapOne(String jsonString)throws Exception{
		//The first step is to parse and remove the outermost layer of the array to get all the json strings
		JSONArray jsons = JSONArray.fromObject(jsonString);
		
	    List<Map<String, String>>  nodes = new ArrayList<Map<String, String>>();
	    //loop through all json substrings
	    for (Object o : jsons)
	    {
	        JSONObject jsonNode = JSONObject.fromObject (o);
	        Map<String, String> treeNodes = new HashMap<String, String>();
	        String rating = "";
	        JSONArray ratingArray = JSONArray.fromObject(jsonNode.getString("rating").trim());
	        for(Object ob : ratingArray) {
	        	rating += ob.toString()+",";
	        }
	        treeNodes.put("rating",rating);
	        treeNodes.put("rank",jsonNode.getString("rank").trim());
	        nodes.add(treeNodes);
	    }
	    return nodes;
	}
	
	/**Parse the case where the outermost part of the json string is {}
	 * {"data":[{"directors":["Putepong Prosaka na Sakna Kalin","Watson Pokpen"],"rate":"8.3"}, {"directors":["David Fincher"],"rate":"8.7"}]}
	 * @throws Exception
	 */
	public List<Map<String, String>> toMapTwo(String jsonString)throws Exception{
		//First convert the jsonString string to jsonObject
		JSONObject jsonNode = JSONObject.fromObject(jsonString);
		//Then get the value of data in json
		JSONArray jsonArray = JSONArray.fromObject(jsonNode.getString("data"));
		List<Map<String, String>>  nodes = new ArrayList<Map<String, String>>();
		// loop through the values ​​in data
		for (Object object : jsonArray) {
			JSONObject jsonNode2 = JSONObject.fromObject(object);
	        Map<String, String> treeNodes = new HashMap<String, String>();
	        treeNodes.put("directors",jsonNode2.getString("directors"));
	        treeNodes.put("rate",jsonNode2.getString("rate").trim());
	        nodes.add(treeNodes);
		}
		return nodes;
	}
	public static void main(String[] args) throws Exception {
		String jsonString = "[{\"rating\":[\"9.6\",\"50\"],\"rank\":1},{\"rating\":[\"9.6\",\"50\"],\"rank\":2}]";
		String jsonString2 = "{\"data\":[{\"directors\":[\"Putepong Prosaka na Saknakarin\",\"Watson Pokpen\" ],\"rate\":\"8.3\"},{\"directors\":[\"David Fincher\"],\"rate\":\"8.7\"}]}";
		JsonToObject jo = new JsonToObject();
		List<Map<String, String>> listMap = jo.toMapOne(jsonString);
		List<Map<String, String>> listMap2 = jo.toMapTwo(jsonString2);
		//The json data is obtained above and encapsulated into the list collection, and the list
		//It encapsulates the map collection
		for (Map<String, String> map : listMap) {
			String rating = map.get("rating");
			String rank  = map.get("rank");
			System.out.println("rating: "+rating);
			System.out.println("rank: "+rank);
		}
		for (Map<String, String> map : listMap2) {
			String directors = map.get("directors");
			String rate = map.get("rate");
			System.out.println("directors: "+directors);
			System.out.println("rate: "+rate);
		}

	}
}

　　Result of running:

For the variable value situation of function debugging in toMapOne: