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Specialized for type MyClass

This Comparator is specialized to compare two objects of the class named MyClass . The first two statements in Listing 6 above confirm that both of the incoming objects are of type MyClass . If either object is not of that type, an exception is thrown.

General behavior of compare method

The general description of the behavior of the compare method as provided by Oracle is shown below:

"Compares its two arguments for order. Returns a negative integer, zero, or a positive integer as the first argument is less than, equal to, orgreater than the second."

Implementation of required behavior

This behavior is accomplished by the code shown in Listing 7 . In this case, the comparison is based solely on the values of the instance variablenamed data in each of the two objects.

Depending on which object contains the larger value in its instance variable, a value of 1 or -1 is returned. If the two values are equal, a value of 0is returned.

(Note that it is up to the author of the compare method to decide what constitutes larger. This gives the author of themethod a great deal of control over the results of a sorting operation.)
Listing 7 . Implementation of required behavior.
if(((MyClass)o1).data<((MyClass)o2).data) return -1;if(((MyClass)o1).data>((MyClass)o2).data) return 1;else return 0; }//end compare()

Other stipulations

The documentation for the compare method contains several other stipulations regarding the behavior of the method. While I believe thatthis version of the compare method meets all of those stipulations, I haven't taken the time to test it fully. Therefore, it is possible that itmay not meet all of the stipulations in terms of its behavior.

The equals method

Every new class inherits a default version of the equals method from the class named Object. Therefore, a new class that implements the Comparator interface already has such a method. The new class is free to override the inherited version, or to simply make use of the inheritedversion. Here is what Oracle has to say on the subject:

"Note that it is always safe not to override Object.equals(Object). However, overriding this method may, in some cases, improve performance byallowing programs to determine that two distinct Comparators impose the same order."

Overridden equals method

I decided, for purposes of illustration, to go ahead and override the equals method. However, my overridden version, as shown in Listing 8 isn't very significant. It simply confirms that an object being comparedfor equality to a Comparator object is instantiated from the same class.

Since the Comparator object doesn't contain any instance variables, there isn't much more to be tested for equality.

Listing 8 . The overridden equals method.
public boolean equals(Object o){ if(!(o instanceof TheComparator))return false; else return true;}//end overridden equals() }//end class TheComparator

The program output

Finally, the code shown in Listing 9 uses an Iterator to display the contents of the populated TreeSet object.

Questions & Answers

so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
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
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Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
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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
what is system testing
what is the application of nanotechnology?
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
anybody can imagine what will be happen after 100 years from now in nano tech world
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
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how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
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I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
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
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bamidele Reply
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Smarajit Reply
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