JSON Streaming API to Read JSON

---

In this tutorial we are going to see how to read JSON from file using JsonParser class available in Jackson.Jackson Streaming API is high-performance Java API for read write JSON.
JsonGenerator – is used to write JSON as String and File.
1. Create project called JSONExample.
2. Create package called com.javatutorialscorner.jackson 
3. add jackson-mapper-asl-1.9.13.jar, jackson-core-asl-1.9.13.jar into build path.
4. Create java class called JSONParserExample under com.javatutorialscorner.jackson
JSONParserExample.java

package com.javatutorialscorner.jackson;

import java.io.File;
import java.io.IOException;

import org.codehaus.jackson.JsonFactory;
import org.codehaus.jackson.JsonParseException;
import org.codehaus.jackson.JsonParser;
import org.codehaus.jackson.JsonToken;

public class JSONParserExample {

 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  JsonFactory factory = null;
  JsonParser jsonParser = null;

  try {
   factory = new JsonFactory();
   jsonParser = factory.createJsonParser(new File(
     "C:\\jtc\\javatutorialscorner.json"));
   while (jsonParser.nextToken() != JsonToken.END_OBJECT) {

    String field = jsonParser.getCurrentName();
    if ("name".equals(field)) {
     jsonParser.nextToken();
     System.out.println("Name : " + jsonParser.getText());
    } else if ("rank".equals(field)) {
     jsonParser.nextToken();
     System.out.println("Rank : " + jsonParser.getIntValue());
    } else if ("Tutorials".equals(field)) {
     jsonParser.nextToken();
     while (jsonParser.nextToken() != JsonToken.END_ARRAY) {
      System.out.println("Tutorials : "
        + jsonParser.getText());
     }
    }
   }
   jsonParser.close();
  } catch (JsonParseException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }

 }

}

Now run the program see the following output in console.

Name : Java Tutorials Corner

Rank : 1


Tutorials : Java


Tutorials : Servlet


Tutorials : JSP


Tutorials : Struts 1.x


Tutorials : Struts 2.x


Tutorials : Spring


Tutorials : Hibernate


Tutorials : Log4j


Tutorials : JSON


Tutorials : Web Services


Tutorials : JSF


Tutorials : Eclipse

Jackson Java JSON 10/18/2013 07:00:00 pm