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Answer 5

A. Compiler Error

Explanation 5

Public classes in separate files

Java requires that the source code for every public class be contained in a separate file. In this case, the source code for two public classes wascontained in a single file. The following compiler error was produced by JDK 1.3:

Ap155.java:18: class Ap155a is public, should be declared in a file named Ap155a.javapublic class Ap155a{

Back to Question 5

Answer 4

This program produces both of the following:

  • C. 5 10 15
  • B. Runtime Error

Explanation 4

The NoSuchElementException

This program defines, creates, and uses a very simple container object for the purpose of illustrating the NoSuchElementException .

The code in the following fragment shows the beginning of a class named MyContainer from which the container object is instantiated.

class MyContainer{ private int[]array = new int[3];public void put(int idx, int data){if(idx>(array.length-1)){ throw newNoSuchElementException(); }else{array[idx] = data;}//end else }//end put()

A wrapper for an array object

This class is essentially a wrapper for a simple array object of type int . An object of the class provides a method named put , which can be used to store an int value into the array. The put method receives two parameters. The first parameter specifies the index of the elementwhere the value of the second parameter is to be stored.

Throw NoSuchElementException on index out of bounds

The put method tests to confirm that the specified index is within the positive bounds of the array. If not, it uses the throw keyword to throw an exception of the type NoSuchElementException . Otherwise, it stores the incoming data value in the specified index position in the array.

(Note that a negative index will cause an ArrayIndexOutOfBoundsException instead of a NoSuchElementException to be thrown.)

The get method

An object of the MyContainer class also provides a get method that can be used to retrieve the value stored in a specified index.

public int get(int idx){ if(idx>(array.length-1)){ throw newNoSuchElementException(); }else{return array[idx];}//end else }//end put()

The get method also tests to confirm that the specified index is within the positive bounds of the array. If not, it throws an exceptionof the type NoSuchElementException . Otherwise, it returns the value stored in the specified index of the array.

(As noted earlier, a negative index will cause an ArrayIndexOutOfBoundsException instead of a NoSuchElementException to bethrown.)

The NoSuchElementException

Thus, this container class illustrates the general intended purpose of the NoSuchElementException .

Instantiate and populate a container

The remainder of the program simply exercises the container. The code in the following fragment instantiates a new container, and uses the put method to populate each of its three available elements with the values 5, 10,and 15.

void doIt(){ MyContainer ref =new MyContainer(); ref.put(0,5);ref.put(1,10); ref.put(2,15);

Questions & Answers

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
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
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
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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