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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

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
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
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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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