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Note that the output file is simply a text file with the extension .json . Thus it can be read by any program that is capable of reading plain text files.

The end of the program

Listing 6 also signals the end of the main method and the end of the program.

The contents of the output file

Figure 1 shows a "prettified" version of the contents of the output file.

Figure 1. Prettified version of output file contents. {"game": [{ "cards":[ "2-club","3-heart","4-diamond","5-spade"],"name":"Tom" },{ "cards":[ "4-heart","5-heart","6-club","7-diamond"],"name":"Joe" }] }

The actual contents of the file do not contain line breaks and indentation as shown in Figure 1 . Those cosmetic features were added manually to Figure 1 to make it easier for you to correlate the output with the code shown earlier. Instead, the actual file consists simply of a string ofcharacters that begins as shown in Figure 2 .

Figure 2. Beginning of output file contents. {"game":[{"cards":["2-club","3-heart","4-diamond","5-spade"],...

Decoded output data

As mentioned earlier, a later page in this book will read the JSON string from the file and decode it into its component parts. Figure 3 shows a preview of what you will see on that page.

Figure 3. Decoded output data. First Player's Name: Tom First Player's cards2-club 3-heart4-diamond 5-spadeSecond Player's Name: Joe Second Player's cards4-heart 5-heart6-club 7-diamond

Figure 3 shows the JSON string decoded and formatted into a display that is representative of the intent of the string -- to encapsulate information aboutthe players and their cards in a game of cards.

Run the program

I encourage you to copy the code from Listing 7 . Execute the code and confirm that your output file matches that shown in Figure 2 . Experiment with the code, making changes, and observing the results of your changes. Make certain that youcan explain why your changes behave as they do.

Complete program listing

Listing 7 provides a complete listing of the program named Code.java .

Listing 7 . The program named Code.java. /************************************************ Copyright: R.G.Baldwin 2016Revised: 06/01/16 Creates a json string and writes it to an outputfile. The json string contains an array, which in turn contains two arrays.Tested with Java 8, Windows 7, and json-simple-1.1.1.************************************************/ 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");//Create and populate a json array, which is// a subclass of the Java ArrayList class. JSONArray arrayListA = new JSONArray();arrayListA.add("2-club"); arrayListA.add("3-heart");arrayListA.add("4-diamond"); arrayListA.add("5-spade");//Populate the json object with a key/value// pair where the value is an array. hashMapA.put("cards",arrayListA);//Create and populate another similar json// object. JSONObject hashMapB = new JSONObject();hashMapB.put("name","Joe");JSONArray arrayListB = new JSONArray(); arrayListB.add("4-heart");arrayListB.add("5-heart"); arrayListB.add("6-club");arrayListB.add("7-diamond"); hashMapB.put("cards",arrayListB);//Create another json array and populate// it with the two json objects created // earlier.JSONArray arrayListC = new JSONArray(); arrayListC.add(hashMapA);arrayListC.add(hashMapB); //Create another json object and populate// it with a key/value pair where the value // is the array from above.JSONObject hashMapC = new JSONObject(); hashMapC.put("game",arrayListC);try{//Encode the HashMap object into a // json String and write it to an output// file. Note that it is simply a text file // with a different extension.PrintWriter out = new PrintWriter(new File("junk.json"));hashMapC.writeJSONString(out); out.flush();}catch(IOException ex){ ex.printStackTrace();}//end catch }//end main}//end class Code

Miscellaneous

This section contains a variety of miscellaneous information.

Housekeeping material
  • Module name: Json0225: Encoding JSON Arrays
  • File: Json0225.htm
  • Published: 06/01/16
Disclaimers:

Financial : Although the Connexions site makes it possible for you to download a PDF file for thismodule at no charge, and also makes it possible for you to purchase a pre-printed version of the PDF file, you should beaware that some of the HTML elements in this module may not translate well into PDF.

I also want you to know that, I receive no financial compensation from the Connexions website even if you purchase the PDF version of the module.

In the past, unknown individuals have copied my modules from cnx.org, converted them to Kindle books, and placed them for sale on Amazon.com showing me as the author. Ineither receive compensation for those sales nor do I know who does receive compensation. If you purchase such a book, please beaware that it is a copy of a module that is freely available on cnx.org and that it was made and published withoutmy prior knowledge.

Affiliation : I am a professor of Computer Information Technology at Austin Community College in Austin, TX.

-end-

Questions & Answers

In few words, what is the role of interest rate in economy?
Carlos Reply
what is population
Nyakeh Reply
total number of people in a given area or country
Clement
the total number of people at a given area or country
Clement
total number of people in a given area or country
okhiria
What is price Elasticity of demand?.
Samuel
The responsiveness of the quantity of a commodity demanded to a change in its price, expressed as the percentage change in quantity demanded divided by the percentage change in price.
EMMANUEL
please rice and beans will be what type of demand but note we mostly cook it together
Oladosu Reply
complementary or joint demand
Yillah
but did you know you can demand for rice without beans so how is it joint or complementary
Oladosu
From my point of view, rice and beans are replaceable goods, hence they can't be complementary.
Carlos
what are the money value
Wisdom Reply
Nothing more than a purchase power, in other words, $100 now, must have the same value after 1 year.
Carlos
what is Monopoly
Rebecca Reply
what is money
Lawal Reply
It can be define as a big transaction that can control any business for one place to another base.
Akinlo
money is recognisable note to accept both parties selling and buying
Hassan
i don still understan
Rene
hey
Abdul
hi
Rene
money is anything generally accepted as a medium of exchange
Awwal
Money is anything generally accepted as a medium of exchange and for the settlement of goods and services .
Korda
hi good ppl, pls help out
Tumi
discuss human and natural resources as develop strategies ro improving living condition of citizens in developing countries.
Tumi
I don't understand the question.
Naomi
it's a form of currency used for 2 or more individuals or parties in order to reach their amicable personal or business attainment. one must understand that money itself can manifest in multiple fashions for which the individuals or parties adheres.
are u trying to say we shld discuss ways in which human natural resources help in improving living condition of citizens in developing countries?
Naomi
money is a legal thunder generally accepted as a medium of exchange for the payment of debt ,goods and services
Naomi
money is a way of payment.
Carlos
money is any thing that is generally accepted as a medium of exchange good for good and settlement of debt and means of payment
Yillah
money is nothing but a object which is used for exchange of goods and services.
Harshita
money is anything that is generally accepted as payment of goods and services and settlement of debt
Rebecca
what is demand
Melissa Reply
demand is where the customer is willing and able to buy goods and services during a given period of time
idk
demand is the ability and willingness of an individual to buy goods and services at a given price in a particular period of time
Alpha
demand is the ability to buy a specific quantities of goods and services at a given price and at a specific period of time
rosemary
what are the rules of demand
rosemary
Rosemary Nsebon, Do you mean laws of demand?
Alpha
what are the rules of demand
Rene
the rule of demand is the higher the price the lower the quantity demanded and the lower the price the higher the quantity demanded
mbi
thank
Rene
what is unemployment
Rebecca
unemployment is a scenario or a phenomenon in an economy whereby people are willing are able to work but cannot a job
mbi
Suppose you have a team of two workers: one is a baker and one is a chef. Explain why the kitchen can produce more meals in a given period of time if each worker specializes in what they do best than if each worker tries to do everything from appetizer to dessert. please I need a urgent answer
Oladosu Reply
Enables individuals and countries to consume a variety of goods and services
Iddrisu
what is the meaning of competency
Oladosu Reply
competency is an ability and courage to do something perfectly
Abdullahi
ability to perform some task
Segun
rival
Ray
thanks 🙏 it is also the same with the core competency
Oladosu
A sufficient supply
Ebenezer
Ebenezer you mean the (core competency) right?
Oladosu
what is mean,median and mode
Ikeh Reply
mean is the average number of a given data
Gallant
median is the middle number of a given data
Gallant
in a given data sorry
Mitchel
hi
Sajib
Pls am new here
Physcal
what are development bank in Nigeria
Adedigba Reply
.hi
Physcal
hi
Adedigba
hw
Physcal
and cool
Rosie
nice to meet everyone
Rosie
hi how are dears
Mumtaz
how can we development economic in our country
Mumtaz
hi
Charm
Payroll and​ 4p
Wasuroj
Agriculture
Wasuroj
Export
Wasuroj
Transport
Wasuroj
Change management​ and​ cerrancy
Wasuroj
Empoyee
Wasuroj
Lawyer army and​ Lawyer​
Wasuroj
animal husbandry essay
Rakuane Reply
what's the primary location of capital and money market respectively
ALIMI
what is bank
Nyakeh Reply
A bank is an institution set up purposely for the save keeping of money and other valuables
Alpha
A bank is a financial institution which helps people to save their money
Cyprian
pls define the HRM and HRP
Mumtaz
we have no money in bank....the bank owes us
Ray
When a supply curve start from the origin price elasticity of supply is unitory. Provide a simple proof
Felix Reply
Oui
Bobbo
please help someone should help me this question
Felix
ok
Anita
what is price
Divine Reply
the perchesing amount of something is called price
Nasir
Researchers demonstrated that the hippocampus functions in memory processing by creating lesions in the hippocampi of rats, which resulted in ________.
Mapo Reply
The formulation of new memories is sometimes called ________, and the process of bringing up old memories is called ________.
Mapo Reply
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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
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