<< Chapter < Page Chapter >> Page >
Learn how to encode JSON array data using the JSONArray class. Also learn how to write an encoded JSON string to an output text file for transport to a different computing environment.

Revised: Thu Jun 02 19:27:08 CDT 2016

This page is included in the following Books:

Table of contents

Preface

This is a page from the book titled The json-simple Java Library . The book explains how to use the json-simple Java library to generate, transform, and query JSON text. This page explains how to encode JSON array data using the JSONArray class. It also shows how to write an encoded JSON string to an output text file for transport to a different programmingenvironment.

Viewing tip

I recommend that you open another copy of this module in a separate browser window and use the following links to easily find and view the Figuresand Listings while you are reading about them.

Figures

  • Figure 1 . Prettified version of output file contents.
  • Figure 2 . Beginning of output file contents.
  • Figure 3 . Decoded output data.

Listings

  • Listing 1 . Beginning of the class and the main method.
  • Listing 2 . Instantiate and populate a JSONArray object.
  • Listing 3 . Populate hashMapA.
  • Listing 4 . Create and populate another similar JSON object.
  • Listing 5 . Put the players in the game.
  • Listing 6 . Write the JSON string to an output file.
  • Listing 7 . The program named Code.java.

General background information

As you learned in the page titled Json0210: Structure of the json-simple Java Library , the JSONArray class extends the standard Java ArrayList class. Once you have an object of the JSONArray class, you have access to all of the methods defined in and inherited into the JSONArray class.

The sample program that follows will use the JSONArray class to construct a JSON string containing nested arrays and will then write thestring to an output file suitable for transport to a different programming environment.

A later page in this book will read the JSON string from the file and decode it into its component parts.

Discussion and sample code

The program named Code (see Listing 7 ) creates a JSON string and writes it to an output file. The json string contains an array, which in turn contains two nested arrays.

Beginning of the class and the main method

I will discuss and explain the program in fragments. The first fragment is shown in Listing 1 .

Listing 1 . Beginning of the class and the main method. import org.json.simple.JSONObject; import org.json.simple.JSONArray;import java.io.PrintWriter; import java.io.File;import java.io.IOException; class Code{public static void main(String[] args){//Create a json object. which is a subclass // of the Java HashMap class.JSONObject hashMapA = new JSONObject();//Populate the json object with a key/value // pair.hashMapA.put("name","Tom");

Questions & Answers

Discuss the differences between taste and flavor, including how other sensory inputs contribute to our  perception of flavor.
John Reply
taste refers to your understanding of the flavor . while flavor one The other hand is refers to sort of just a blend things.
Faith
While taste primarily relies on our taste buds, flavor involves a complex interplay between taste and aroma
Kamara
which drugs can we use for ulcers
Ummi Reply
omeprazole
Kamara
what
Renee
what is this
Renee
is a drug
Kamara
of anti-ulcer
Kamara
Omeprazole Cimetidine / Tagament For the complicated once ulcer - kit
Patrick
what is the function of lymphatic system
Nency Reply
Not really sure
Eli
to drain extracellular fluid all over the body.
asegid
The lymphatic system plays several crucial roles in the human body, functioning as a key component of the immune system and contributing to the maintenance of fluid balance. Its main functions include: 1. Immune Response: The lymphatic system produces and transports lymphocytes, which are a type of
asegid
to transport fluids fats proteins and lymphocytes to the blood stream as lymph
Adama
what is anatomy
Oyindarmola Reply
Anatomy is the identification and description of the structures of living things
Kamara
what's the difference between anatomy and physiology
Oyerinde Reply
Anatomy is the study of the structure of the body, while physiology is the study of the function of the body. Anatomy looks at the body's organs and systems, while physiology looks at how those organs and systems work together to keep the body functioning.
AI-Robot
what is enzymes all about?
Mohammed Reply
Enzymes are proteins that help speed up chemical reactions in our bodies. Enzymes are essential for digestion, liver function and much more. Too much or too little of a certain enzyme can cause health problems
Kamara
yes
Prince
how does the stomach protect itself from the damaging effects of HCl
Wulku Reply
little girl okay how does the stomach protect itself from the damaging effect of HCL
Wulku
it is because of the enzyme that the stomach produce that help the stomach from the damaging effect of HCL
Kamara
function of digestive system
Ali Reply
function of digestive
Ali
the diagram of the lungs
Adaeze Reply
what is the normal body temperature
Diya Reply
37 degrees selcius
Xolo
37°c
Stephanie
please why 37 degree selcius normal temperature
Mark
36.5
Simon
37°c
Iyogho
the normal temperature is 37°c or 98.6 °Fahrenheit is important for maintaining the homeostasis in the body the body regular this temperature through the process called thermoregulation which involves brain skin muscle and other organ working together to maintain stable internal temperature
Stephanie
37A c
Wulku
what is anaemia
Diya Reply
anaemia is the decrease in RBC count hemoglobin count and PVC count
Eniola
what is the pH of the vagina
Diya Reply
how does Lysin attack pathogens
Diya
acid
Mary
I information on anatomy position and digestive system and there enzyme
Elisha Reply
anatomy of the female external genitalia
Muhammad Reply
Organ Systems Of The Human Body (Continued) Organ Systems Of The Human Body (Continued)
Theophilus Reply
what's lochia albra
Kizito
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Object-oriented programming (oop) with java. OpenStax CNX. Jun 29, 2016 Download for free at https://legacy.cnx.org/content/col11441/1.201
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Object-oriented programming (oop) with java' conversation and receive update notifications?

Ask