Jackson Steaming API

Jackson Steaming API
Hello friends.hope you are fine  .today i am going to demonstrate how to process json data.there are various API's available in market ,here i am going to demonstrate you Jackson Streaming API Code.

it is  API used for processing json data.how ever it process the data/token  in incremental manner. it treats individual token as a element.it is faster & convinient way of processing json data.

below sample code  creates json file using Jackson Streaming API:


package org.demo;
import java.io.File;
import java.io.IOException;

import org.codehaus.jackson.JsonEncoding;
import org.codehaus.jackson.JsonFactory;
import org.codehaus.jackson.JsonGenerator;

public class JacksonReader
{

        public static void main(String []args) throws IOException
        {
            JsonFactory jfactory =new JsonFactory();
           
            JsonGenerator jgenerator=jfactory.createJsonGenerator(new File("D:\\ocjp\\Data.json"),JsonEncoding.UTF8);//used to write data in streaming way
           
                jgenerator.writeStartObject();//{
               
                jgenerator.writeStringField("Name","Akshita");//"Name":Akshita
               
                jgenerator.writeNumberField("Age",21);//"Age":21
               

       jgenerator.writeFieldName("hobby");//"messages" 

                jgenerator.writeStartArray(); //[
               
                jgenerator.writeString("Reading");//"Reading"
                jgenerator.writeString("Coding");//"Coding"
                jgenerator.writeString("Surfing");://"Surfing"
               
               
                jgenerator.writeEndArray(); //]
               
               
                jgenerator.close();//close the document
               
       
       
        }
}

Sample data.json file that will be generated after compiliation of the above code:

{ "Name":Akshita
 "Age":21 ,
"hobby":["Reading","Coding","Surfing"]
};

below code show how to read json data from json file:

import java.io.File;
import java.io.IOException;
import org.codehaus.jackson.JsonFactory;
import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.JsonParser;
import org.codehaus.jackson.JsonToken;
import org.codehaus.jackson.map.JsonMappingException;

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

     try {

    JsonFactory jfactory = new JsonFactory();

    /*** read from file ***/
    JsonParser jParser = jfactory.createJsonParser(new File("D://ocjp//Data.json"));

    // loop until token equal to "}"
    while (jParser.nextToken() != JsonToken.END_OBJECT) {

        String fieldname = jParser.getCurrentName();
        if ("Name".equals(fieldname)) {

         
          jParser.nextToken();
          System.out.println(jParser.getText());

        }

        if ("age".equals(fieldname)) {

         
          jParser.nextToken();
          System.out.println(jParser.getIntValue()); // display 29

        }

        if ("hobyy".equals(fieldname)) {

          jParser.nextToken(); // current token is "[", move next

          // messages is array, loop until token equal to "]"
          while (jParser.nextToken() != JsonToken.END_ARRAY) {

                     // display Reading,Surfing
             System.out.println(jParser.getText());

          }

        }

      }
      jParser.close();

     } catch (JsonGenerationException e) {

      e.printStackTrace();

     } catch (JsonMappingException e) {

      e.printStackTrace();

     } catch (IOException e) {

      e.printStackTrace();

     }

  }

}

thanks
for any query ping me on pathak.nisarg@yahoo.com