<< Chapter < Page Chapter >> Page >
Every Java application requires a class containing a method named main. This module provides information on the main method.

Revised: Mon Mar 28 11:21:22 CDT 2016

This page is included in the following Books:

Table of contents

Preface

This module is part of a collection of modules designed to help you learn to program computers.

Every Java application requires a class containing a method named main . This module provides information on the main method.

Viewing tip

I recommend that you open another copy of this module in a separate browser window and use the following links to easily find and view the Figureswhile you are reading about them.

Figures

  • Figure 1 . The method signature according to Niemeyer and Peck.
  • Figure 2 . The method signature according to Oracle.
  • Figure 3 . Allowable signatures for the main method.

The main method in Java

There must be a main method in the controlling class in every Java application.

The method signature

The Java literature frequently refers to the signature of a method, or the method signature .

Exploring Java by Patrick Niemeyer and Joshua Peck (O'Reilly) provides the definition of a method signature shown in Figure 1 .

Figure 1. The method signature according to Niemeyer and Peck .
"A method signature is a collection of information about the method, as in a C prototype or a forward function declaration in other languages. It includesthe method's name, type, and visibility, as well as its arguments and return type."

Type

Apparently in this definition, the authors are referring to the type of the method as distinguishing between static and non-static. (Other literature refers to the type of a function or method as being the return typewhich according to the above definition is a separate part of the signature.)

Visibility

Apparently also the use of the word visibility in the above definition refers to the use of public , private , etc.

According to Oracle...

Oracle's Java Tutorials , on the other hand, describe the method signature as in Figure 2 .

Figure 2. The method signature according to Oracle .
Definition: Two of the components of a method declaration comprise the method signature -- the method's name and the parameter types.

As you can see, the Oracle definition is more restrictive than the Niemeyer and Peck definition.

Bottom line on method signature

The method signature can probably be thought of as providing information about the programming interface to the method. In other words, it provides the information that you need to be able to call themethod in your program code.

Signature of main method

The controlling class of every Java application must contain a main method having one of the signatures shown in Figure 3 .

Figure 3 . Allowable signatures for the main method.
public static void main(String[] args)public static void main(String args[])

(I prefer the first signature in Figure 3 as being the most descriptive of an array of String references which is what is passed in as an argument.)

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
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
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!





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
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Object-oriented programming (oop) with java' conversation and receive update notifications?

Ask
Vanessa Soledad
Start Exam
Sheila Lopez
Start Exam
Yasser Ibrahim
Start Quiz