Calling main method of a class

Hi
I have to call the Main method of a class in some other class becuass that class is accepting command line aurguments.
I test it and everything is working fine.
           String[] strings = new String[3];
           strings[0] = "E:/practice.cap";
           strings[1] = "-o";
           strings[2] = "E:/practice.txt";
           Main.main(strings);I now want to know is there any drawback of doing this ?
BR
regards

Muhammad Umer wrote:
Good Explanation. But my question is not to explain the importance of main method in classes :)As far as the Java language and APIs go, there's nothing wrong with calling main just like any other method, because it is just another method. It's only special to the JVM, and to programmers who assume that it's the entry point to the program.
As far as Java is concerned, you can call as many mains as you want. The only potential problem arises if some particular main is written in a way that relies on it being the entry point to the whole program. That is, if the author wrote it with the assumption that it would only be called by the JVM at startup time, and would not be called arbitrarily from within your code (EDIT: and if proper behavior relies on that assumption being upheld). However, this is just a particular case of a general issue that we always have to be aware of, namely, make sure you understand how a method is intended to be used, and use it in that fashion, or accept the consequences.
EDIT: However, having said that, it's unusual to call main explicitly, so if you can, I would suggest pulling the functionality that you want out of that main into a different method, and then both your code and the main can call that method. If you cannot do that, then at the point where you call main, clearly document why you're doing it. Otherwise, whoever reads the code a few months or years from now--maybe somebody else, maybe you--will be wondering if the programmer really knew what he was doing, or if that is a mistake. That kind of second-guessing is the source of a lot of maintenance nightmares.
Edited by: jverd on Nov 3, 2011 8:43 AM

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Can we call main method in another class?

Hi...
can we call main method in another class?
If no, please tell me the exact reason why can't we call that....

ok
can u give that code for me?
class A {
public static void main(String [] args){
System.out.println("In A");
class B {
public static void main(String [] args){
A.main(null);
}

Calling main method in another class using command line arguements

Hi
My program need to use 4 strings command line arguments
entered in Project properties/Run/Application Parameters
java programming for beginners // arguments
The program needs to call main in the second class 4 times using argument 1 the first call, argument 2 the second call on so on.
So the output wil be
java
programming
for
beginners
import java.lang.*;
public class First extends Second{
public static void main(String[] args) {
for(int i = 0; i < args.length; i++){
Second.main(args); // Error I think
import java.lang.*;
public class Second {
public static void main(String[] args){
System.out.println(args[0]);
"First.java": Error #: 300 : method main(java.lang.String) not found in class Second at line 6, column 15
I am only a beginner with little knowledge of java so can the code be as basic as possible

Your style looks quite bad for starters..... Hows
this://import java.lang.*; /* NOT NEEDED */
public class First extends Second{
public First(String s) {
super(s);
public static void main(String[] args) {
for(int i = 0; i < args.length; i++){
new First(s);
public class Second {
public Second(String s)
System.out.println(s);
NOT NEEDED:
public static void main(String[] args){
System.out.println(args[0]);
}My question to you: Do you understand why my code
works? (does it do what you want?)I think since this is some kind of lesson, the OP have to implement some way to use the main method of the Second class as it is, that is, with String[] args. I think this lesson is interesting exactly because of this requirenment. But, anyway, I don�t know, that is just my assumption...

How to call main method in one class from another class

Suppose i have a code like this
class Demo
public static void main(String args[])
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class Demo1
public static void main(String args[])
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In the above program how to call main method in demo calss from Demo1 class......???????

No, i dont know how to call other than main methods from other classes
And one more doubt i have i.e. Like in C can we see the execution of the program like how the code is being compiled step by step and how the value of the variable changes from step to step like(Add Watch).........

How do you call a java class from the main method in another class?

Hi all,
How do you call a java class from the main() method in another class? Assuming the two class are in the same package.
Thanks
SI
Edited by: okun on May 16, 2010 8:40 PM
Edited by: okun on May 16, 2010 8:41 PM
Edited by: okun on May 16, 2010 8:47 PM

georgemc wrote:
To answer your impending question, either the method you're calling has to be static, or you need an instance of that other class to invoke it against. Prefer the latterAnd to your impending question after that: no, don't use the Singleton pattern.

How to call particular method in action class from Portlets StrutsContent

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Edited by: user13634949 on Jun 23, 2011 1:22 PM
Edited by: user13634949 on Jun 23, 2011 1:22 PM

No, i dont know how to call other than main methods from other classes
And one more doubt i have i.e. Like in C can we see the execution of the program like how the code is being compiled step by step and how the value of the variable changes from step to step like(Add Watch).........

How to call a method of another class ?

Hello,
I�d like to know how to call a method of another class. I have to classes (class 1 and class 2), class 1 instantiates an object of class 2 and executes the rest of the method. Later, class 1 has to call a method of class 2, sending a message to do something in the object... Does anybody know how to do that ? Do I have to use interface ? Could you please help me ?
Thanks.
Bruno.

Hi Schiller,
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import java.awt.*;
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[]�s.

How to call a method from another class

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Main method in mulitple classes?

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Edited by: LIVE3A17 on Apr 28, 2009 3:13 PM

LIVE3A17 wrote:
Ok, so I can use main methods in the other classes, and java knows which is the main class by which one is opened when the program is run. Got it. Don't even put a main method in the other classes, unless you intend on one of them to be an entry point. Otherwise it's just code bloat.
>
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Calling main method of a class

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