Check out example codes for "how to read a .json from web api java". It will help you in understanding the concepts better.

Code Example 1

try {
			URL url = new URL("url");
			HttpURLConnection conn = (HttpURLConnection)url.openConnection();
			conn.setRequestMethod("GET");
			conn.connect();
			if(conn.getResponseCode() == 200) {
				Scanner scan = new Scanner(url.openStream());
				while(scan.hasNext()) {
					String temp = scan.nextLine();
                  	//parse json here
                }
            }
}

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