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The code in Listing 1 instantiates two objects of the class named ArrayList to serve as containers for the JSONObject objects and the JSON strings. This is plain vanilla Java code. There is nothing new here.

Create and populate a JSONObject object

Listing 2 creates and populates the first JSONObject object with key/value pairs. The keys are "name", "age", and "student" respectively. The value types are String , int , and boolean respectively.

Listing 2 . Create and populate a JSONObject object. listA.add(new JSONObject());listA.get(0).put("name","Joe"); listA.get(0).put("age",21);listA.get(0).put("student",true);

The code in Listing 2 begins by instantiating a new object of the JSONObject class and adding its reference into the first element (0) of the ArrayList object. Then it calls the get method on the ArrayList object three times in succession to gain access to the JSONObject . Each time it gains access to the JSONObject object, it calls the put method inherited from the HashMap class to store a key/value pair in the JSONObject object.

Note that the data stored in the JSONObject object is an unordered collection. As you will see later, the order inwhich the key/value pairs are extracted from the object using an iterator is unrelated to the order in which the key/value pairs are stored in the object.

Create and populate two more JSONObject objects

Listing 3 repeats the process two more times to create, populate, and save two more JSONObject objects. Note that one of these objects is populated in a different order than is the case in Listing 2 .

Listing 3 . Create and populate two more JSONObject objects. //Create and populate the second JSONObject. listA.add(new JSONObject());listA.get(1).put("student",false); listA.get(1).put("name","Sue");listA.get(1).put("age",32);//Create and populate the third JSONObject listA.add(new JSONObject());listA.get(2).put("name","Tom"); listA.get(2).put("age",19);listA.get(2).put("student",true);

Encode the data into JSON strings

Listing 4 uses an Iterator to gain access to each populated JSONObject object. Each time it gains access to an object, it calls the toJSONString method that is defined in the JSONObject class to transform the object into a JSON string.

At this point, the program could write the JSON strings into an output stream for transfer to some other programming environment. However as mentionedearlier, to keep the program simple, the program saves the JSON strings as elements in a second ArrayList object.

Listing 4 . Encode the data into JSON strings. Iterator<JSONObject>iteratorA = listA.iterator(); while (iteratorA.hasNext()){listB.add(iteratorA.next().toJSONString()); }//end while loop

Display the JSON strings

Listing 5 uses an Iterator to access and display each of the JSON strings that are stored in the ArrayList object.

Listing 5 . Display the JSON strings. Iterator<String>iteratorB = listB.iterator(); while (iteratorB.hasNext()){System.out.println(iteratorB.next()); }//end while loop}//end main }//end class Code

The screen output is shown in Figure 1 .

Questions & Answers

How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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