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Last update:   29-10-2021

Json

! Compare to XML, JSON is much smaller in size.
T 
package com.minte9.collections.json;
import static org.junit.Assert.assertEquals;

import org.json.JSONObject;
import org.junit.Test;

public class JsonTest {

    @Test public void json() {

        String s = "{message:{type:feed,timestamp:1},error:0}";
        JSONObject obj = new JSONObject(s);

        assertEquals("feed", obj.getJSONObject("message").getString("type"));
            // passed
        assertEquals(0, obj.getInt("error"));
            // passed
    }
}

Translate

Custom formats can be easily transtated to Json.
 
/**
 * Translate custom formats to json for easy parsing.
 */

package com.minte9.collections.json;
import org.json.JSONObject;

public class Translate {
    public static void main(String[] args) {

        //String s = "{message:{type:feed,timestamp:1},error:0}"; // json

        String s = "{message={type=feed|timestamp=1},error=0}"; // not a json
        JSONObject obj;

        s = translate(s);
        obj = new JSONObject(s);

        System.out.println(
            obj.getJSONObject("message").getString("type") // feed
        );

        System.out.println(
            obj.getInt("error") // 0
        );
    }
    
    public static String translate(String s) {

        s = s.replaceAll("([^={}|]+)=", "$1="); // add quotes to keys
        s = s.replaceAll("=([^={}|]+)", "=$1"); // add quotes to values
        s = s.replace("|", ",").replace("=", ":");
            // System.out.println(s);

        return s;
    }
}

Loop

To parse json array, use for-each loop with getJSONArray() method.
 
/**
 * Use getJSONArray() in order to loop an json
 */

package com.minte9.collections.json;

import org.json.JSONArray;
import org.json.JSONObject;

public class Loop {
    public static void main(String[] args) {

        String str = "{"
            + "orders: ["
                + "{sym:goog,amount:100,error:1},"
                + "{sym:msft,amount:200,error:0}"
            + "], error:0" +
        "}";

        JSONObject obj = new JSONObject(str);
        JSONArray orders = obj.getJSONArray("orders");
            //System.out.println(orders);

        for(Object item : orders) {

            JSONObject order = (JSONObject) item; // Look Here
            System.out.println(""
                + order.getString("sym") 
                + ":"
                + order.getInt("error")
            );
                // goog:1
                // msft:0
        }
    }
}

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