I am a newbie in Android , I am doing a project where json parsing is done by calling a URL. I am able to do this by using built-in json parser provided by android.
But when i try to parse huge json response ,it fails. I got to know about another parser, "Jackson parser".
I googled a lot,but with no luck.
So , can anybody suggest me a way to parse json using Jackson parser through url?
OR
Provide me some example links, if possible?
I think, It will be helpful to other newbies like me.
You might want to give the package org.json a try. It is provided directly from the Android sdk.
JSONObjects can directly be parsed and provided to your objects i.g. via the constructor.
Try using thed Gson lib to deserialize json objects. Less painful to use, and it supports large objects quite well.
Related
I'm trying to write/read a json object to/from a file.
The json structure is complex and is dynamically generated.
For small json object I would just transform json to string then do string writing/reading. This causes out of memory issue when the json gets too large.
How do I stream the JSONObject directly to a file, and stream back the JSONObject directly from the file?
Having a quick look at the Android api, it seems that you want functionality similar to JsonStringer (https://developer.android.com/reference/org/json/JSONStringer.html) - but it doesn't seem like it is capable of streaming the results. Other than that, I think you'll be bound to either finding a suitable library (possibily https://github.com/yonik/noggit) or implementing your own json streamer (which I doubt would be that hard).
I suggest you use GSON, Google's library to handle JSONs. I use it a lot for converting JSON web responses into classes.
https://github.com/google/gson/blob/master/UserGuide.md
I cannot find any explanation about why we use JSON when parsing it in Android?. Are we required to use it or is this just optional? What's the advantage and disadvantage of using it to extract data from the internet? Do we have to encode every data from PHP & MySQL into a JSON Format?
See this question. JSON is known as JavaScript Object Notation, it's a lot easier to parse then XML data, and there are libraries to help you retrieve the values from a JSON structure. As for the PHP & MySQL question, Android doesn't use MySQL, it uses SQLite instead. Hope this helps.
JSON is just a format to represent Objects in textform. Its used often in Android because its nice to work with and has many libraries to help parse it.
Sometimes other formats are used like XML or something else to represent the data.
You can use any communication protocol you want, json is just an accepted standard. You can't just 'dump the mysql database' to the app, there has to be some sort of communication protocol that the server and client agree on to transport the data.
Some alternatives are xml or a binary format (such as protobuf).
I'd recommend json due to the abundance of tools and literature on it.
(Heres a blog post I wrote on using Jackson to parse json in Android http://shmuelrosansky.com/jackson/android/2015/07/20/jackson-android/)
I am going to be consuming real time twitter feed and parsing it into objects for list view display. I need robust solution is default json lib good enough for this task or do I need to use Gson / jackson lib?
Check Gson and JackSon:
GSON
JACKSON
EDIT: I did not see you mention this libraries. Yes, you should use them. This are robust
libraries, I used them to consume Json webservices and no problem so far.
GSON/Jackson are just the libraries that allow you to parse json responses into objects or the other way round. However, the default implementation of json provided in android framework is capable enough of dealing any response string. The only drawback or turn-off is that you need to write extra code for simple things to get done.
Following are some links with bench marking of JSON libs...
http://blog.novoj.net/2012/02/05/json-java-parsers-generators-microbenchmark/
http://danielywoo.blogspot.in/2011/04/json-java-libraries-benchmark-jsonlib.html
Jackson Vs. Gson
And from the benchmark it looks like Jackson is the best and the fastest library for the JSON parsing...
I'm curious whether it's more convenient to use json or xml in my android applications? Or does it not matter?
In Flash apps it's definitely more convenient to use xml, but in javascript (at least in my opinion), it's more convenient to work with json. I have a rails backend that could conveniently give json or xml so I'm trying to make a choice now.
Well the reason i ll recommend JSON not easy of use but the network bandwidth. JSON msgs are smaller in size as compared to XML. So consider this also for choosing one over the other.
Secondly, you can use Gson another lib also to ease your implementation which is easier to use as compared to org.json implementation that comes with Android platform.
JSON would be very easy in Android. You already have libraries for it, whose Classes you can use to parse the JSON file or content.
There is some pain involved in parsing XML. I would suggest JSON. Let me know if you need any examples of parsing using JSON.
Android SDK has both org.json or org.xml package so i think it is not a matter of Android sdk, but of your application/api design
JSON is very easy to use as comparing to XML.Android has support for both JSON and XML.A detailed example is already given here.This talks about when you go for JSON and XML
http://www.ibm.com/developerworks/xml/library/x-andbene1/
Hope this will help you.
In the Android application I am building, I want to be able to communicate with a local server developed in Django. (Basically a login page and a home page populated with posts and images from users) So do I need to use XML Parsers for the parsing the response from a Django server or is it possible for the server to respond with strings which can be directly used? Also what about images?
Is the JSON or XML Parser easier and robust to use in Android? The responses would be basically like tweets with a username, image and message. I was thinking of using the SAXParser. Any better alternatives?
Regards,
Primal
Android has built in libraries for parsing both JSON and XML.
In my opinion, the easier (and better) one would probably JSON if you're just looking to output the serialized version of your models.
Some relevant links:
JSON:
https://developer.android.com/reference/org/json/JSONObject.html
XML:
https://developer.android.com/reference/org/xmlpull/v1/XmlPullParser.html
https://developer.android.com/reference/javax/xml/parsers/package-summary.html
Edit: In response to the last part of your question, yes, you can just output strings. Depending on the complexity of your data, you'll end up making things harder for yourself. Parsing JSON on Android is super easy. Just do it.
SAXParser is very easy to use, it just calls a method when it enters a node with the name of the node and its arguments.
So yes, using SAX is a good idea.