How to Parse JSON String in LWUIT - json

Question

How to parse a JSON object in LWUIT,give me some example or some link from where i can read this.Suppose i have the objects given below.
"{'guild': 'Crimson', 'region': 'us', 'realm': 'Caelestrasz', 'timestamp': 1311860040}"

Answer 1

Json Example Code:This Code will work for json.
package com.ndtv.parser;
import java.io.IOException;
import java.io.InputStream;
import java.util.Vector;
import javax.microedition.io.Connector;
import javax.microedition.io.HttpConnection;
import com.ndtv.callback.jsonActivelistener;
import com.ndtv.datatype.StockActiveItem;
import json.me.JSONArray;
import json.me.JSONException;
import json.me.JSONObject;
public class StockActiveParser {
public Vector jsonObjVector = new Vector();
public JSONArray arrayObj = null;
public String name,LastPrice;
protected jsonActivelistener mjsonListener;
public static boolean ParserCanceled = false;
public void setjsonListener(jsonActivelistener listener) {
mjsonListener = listener;
}
// Non-blocking.
public void parser(final String url) {
Thread t = new Thread() {
public void run() {
// set up the network connection
try {
jsonParse(url);
}
catch (Exception e) {
mjsonListener.parserExceptionListing(e);
}
mjsonListener.parseDidFinishListing();
}
};
t.start();
}
protected void jsonParse(String url) {
StringBuffer stringBuffer = new StringBuffer();
InputStream is = null;
HttpConnection hc = null;
System.out.println(url);
try {
hc = (HttpConnection)Connector.open(url);
is = hc.openInputStream();
int ch;
while ((ch = is.read()) != -1) {
stringBuffer.append((char) ch);
}
}
catch (SecurityException se) {
System.out.println("security exception:"+se);
}
catch (NullPointerException npe) {
System.out.println("null pointer excception:"+npe);
}
catch (IOException ioe) {
System.out.println("io exception:"+ioe);
}
try{
hc.close();
is.close();
}catch(Exception e) {
System.out.println("Error in MostActivePareser Connection close:"+e);
e.printStackTrace();
}
String jsonData = stringBuffer.toString();
try {
JSONObject js = new JSONObject(jsonData);
JSONArray js2 = js.getJSONArray("values");
System.out.println(js2.length());
for (int i = 0; i < js2.length(); i++) {
StockActiveItem item = new StockActiveItem();
JSONObject jsObj = js2.getJSONObject(i);
item.name = jsObj.getString("name");
item.last_traded_price = jsObj.getString("last_traded_price");
item.change = jsObj.getString("change");
item.price_diff = jsObj.getString("price_diff");
item.chart=jsObj.getString("chart");
item.company_id=jsObj.getString("company_id");
mjsonListener.itemParsedListing(item);
}
} catch (JSONException e1) {
System.out.println("Json Data error:"+e1);
e1.printStackTrace();
}
catch (NullPointerException e) {
System.out.println("null error:"+e);
}
}
}
public class StockActiveItem
{
public String name ="";
public String last_traded_price ="";
public String change="";
public String price_diff ="";
public String chart="";
public String company_id="";
public String year_high="";
public String year_low="";
}
you just replace name, for example guild replacing name.If any doubt ask me.

Answer 2

Use LWUIT JSONParser and parser the JSON format string. Just use MIDP_IO.jar from latest LWUIT 1.5 for this.

Answer 3

I was able to use sample code provided in below given links successfully in my app.
http://jimmod.com/blog/2010/03/java-me-j2me-json-implementation-tutorialsample/
http://jimmod.com/blog/2011/09/java-me-j2me-json-implementation-for-array-object/
BTW, Latest JSON ME library can be found here : https://github.com/upictec/org.json.me/

Answer 4

You can use JSON jar and and import that in your project. After that create a JSON object and you can use optString or getString methods of that object accordingly to get the values.