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Populating the LinkedList collection

A couple of points regarding the fillIt method (shown in Listing 4 ) are worthy of note.

Listing 4 . The fillIt method.
public static void fillIt(Collection ref){ ref.add(new JButton());ref.add(new JButton()); ref.add(new JLabel());ref.add(new JButton()); ref.add(new JButton());ref.add(new JLabel()); Iterator iter = ref.iterator();int cnt = 0; JComponent refVar;while(iter.hasNext()){ refVar = (JComponent)iter.next();if(refVar instanceof JButton){ refVar.setToolTipText("B"+cnt++);}else{ refVar.setToolTipText("L" + cnt++);}//end else }//end while loop}//end fillIt()

The fillIt method begins by calling the add method six times in succession, passing references to new anonymous objects (of types JButton and JLabel) as a parameter to the add method.

Four buttons and two labels

Four of the objects are instantiated from the class named JButton . The other two objects are instantiated from the class named JLabel .

Both JButton and JLabel belong to the javax.swing package. Further, both are subclasses of the class named JComponent .

The toolTipText property

Finally, both classes have a property named toolTipText , which can be set and accessed by calling the following methods on a reference to the object:

void setToolTipText(String text) String getToolTipText()

JButton and JLabel

I chose to use objects of these two classes for illustration purposes simply because they possess the characteristics that I need for this module. Thosecharacteristics are:

  • Both classes subclass the class named JComponent (a common superclass below the Object class).
  • Both classes inherit a property (toolTipText) that can be used to identify them later.

Making the objects distinguishable

After adding the objects' references to the collection, the code in Listing 4 uses the setToolTipText method to store a unique String value in the toolTipText property of the object referred to by each of the elements in the collection.

Identifying the buttons and labels

In addition to storing a unique value in the toolTipText property of the object referred to by each element, the code in Listing 4 also makes it possible to distinguish between the JButton objects and the JLabel objects. This is accomplished by including an upper-case "B" in the propertyvalue for each JButton , and including an upper-case "L" in the property value for each JLabel button.

Display the collection

The code in Listing 3 above calls the showCollection method to display the contents of the populated LinkedList collection. The output produced by the code in Listing 3 is shown below:

Collection contents B0 B1 L2 B3 B4 L5

Each term in the output is the String value of the toolTipText property for a particular object. Hence, there are six terms in the output, onefor each element in the collection.

Copy collection elements into an array

Having completed the preliminaries, we have now reached the point that is the main thrust of this module.

The code in Listing 5 shows how to use the more-complex version of the toArray method to copy the elements in the collection into an array.

Questions & Answers

Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
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.
Harper
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
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Cied
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Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
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Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit 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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