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  • The main method calls the method printMax ; the actual parameters are two integer literals.
  • The activation record for printMax is allocated, and the actual parameters are used to initialize the formal parameters a and b .
  • The variable max is allocated but not initialized.
  • The method maximum is called; the actual parameters are the values of a and b , which are the formal variables of method printMax .
  • An activation record is allocated for maximum . (There are now three activation in the stack.) The new activation record includesmemory for the formal parameters a and b ; note that these are new parameters not at all related to the formal parameters of the same namesin the previous method printMax because those parameters are hidden.
  • The method maximum executes its body and returns a value. Just before it returns, select the tab Call Tree above the graphic display; the sequence of calls from main to printMax and then maximum is displayed. Select Theater to return to the animated display.
  • When the method returns, its activation record is deallocated, uncovering the activation record of printMax .
  • The value returned is assigned to the variable max and printed.
  • When printMax completes its execution, its activation record is deallocated.

Note: In a call to a static method, the name of the class in which it is defined can be given as in the call to maximum . Since the method is defined in the same class as the call,the class name need not be given, as shown in the call to printMax .

Exercise Write a program to compute the maximum of six values using as few statements as possible.

Recursion

Concept Recursion occurs when method calls itself. There is nothing at all mysterious about recursion!Each call simply creates a new activation record on the stack. However, to ensure that the recursive calls terminate,eventually, some call of the method should return without invoking itself once again.

Program: Method04.java

// Learning Object Method04 //    recursionpublic class Method04 {     static int factorial (int n) {        if (n <= 1)             return 1;        else             return n * factorial(n-1);    }      public static void main(/*String[] args*/) {        System.out.println(factorial(5));     }}

The standard example of a recursive method is one that computes the factorial function:

n ! = n · ( n - 1 ) · · 2 · 1 = n · ( n - 1 ) !

The recursion is terminated by defining n ! = 1 for n 1 .

  • The main method calls the method factorial with the actual parameter 5. This creates an activation record with the formal parameter n initialized to 5.
  • To compute the expression in the second return statement, the method factorial is called again, this time with the actual parameter equal to 5 - 1 = 4 .
  • The sequence of recursive calls continues five times, each one allocating a new activation record with a new variable n .
  • Finally, factorial is called with actual parameter 1. This call creates a new activation record as usual, but does notcause factorial to be invoked again. Instead, the value 1 is returned and the activation record is deallocated.Just before the method returns, select the tab Call Tree above the graphic display; the sequence of calls from main to the sequence of recursive calls is displayed. Select Theater to return to the animated display.
  • The recursive sequence unfolds : each returned value is used to compute a new value to be returned by that call of factorial .
  • Finally, the value 120 is returned to the main method and printed.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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
Do you know which machine is used to that process?
s.
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
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket 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, Learning objects for java (with jeliot). OpenStax CNX. Dec 28, 2009 Download for free at http://cnx.org/content/col10915/1.2
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