How to create Json Array using Streaming Model API?

package com.javaapi.json.examples;

import java.io.StringWriter;

import javax.json.Json;
import javax.json.stream.JsonGenerator;

public class CreateJsonObjGenEx {

	public static void main(String a[]){
		
		StringWriter strWtr = new StringWriter();
		JsonGenerator jsonGen = Json.createGenerator(strWtr);
		JsonGenerator start = jsonGen.writeStartObject();
		start.write("emp_name", "Nataraj G");
		start.write("emp_id", 1016);
		start.write("salary", 20000);
		
		// create Json array with only values
		JsonGenerator plnArrGen = start.writeStartArray("direct_contacts");
		plnArrGen.write("Rakesh");
		plnArrGen.write("John");
		plnArrGen.writeEnd();
		
		// create an array of key-value pairs
		JsonGenerator kvArrGen = start.writeStartArray("contacts");
		// create each key-value pair as seperate object and add it to the array
		kvArrGen.writeStartObject().write("email", "[email protected]").writeEnd();
		kvArrGen.writeStartObject().write("mobile", "123123123123").writeEnd();
		kvArrGen.writeEnd();
		
		start.writeEnd();
		jsonGen.close();
		
		System.out.println(strWtr.toString());
	}
}

{
    "emp_name": "Nataraj G",
    "emp_id": 1016,
    "salary": 20000,
    "direct_contacts": [
        "Rakesh",
        "John"
    ],
    "contacts": [
        {
            "email": "[email protected]"
        },
        {
            "mobile": "123123123123"
        }
    ]
}