Passign argument to a fucntion at command Line

[Ritika Misra]

hello ranchers,

can any one help me to passs arguments to a fucntion at command line.


example:

  


Class A{

public void abc(String aString b){

//some code

}


public static void main (String args[]){

A a =new A();
a.abc( ....... , .......) ////this is where my paramters shld come from command prompt....

}


}

any help will be appreciated....

[Rok Štelcer]

Hi,

Well, thats why Java's main method has array of Strings.
For example:

public class ReadCmdArgs
{
   public static void main(String[] args)
   {
       // check if user specified any args ... to avoid possible NullPointer exception later
       if (args == null)
       {
           System.out.println("Input args are not available.");
           return;
       }

       // now, lets read the input
       for (int i = 0; i < args.length; i++)
       {
          System.out.println("argument[" + i + "] = " + args[i]);
       }
   }

} 

lets compile and run the code
#javac ReadCmdArgs.java
#java ReadCmdArgs foo1 foo2 foo3

And the output would be:
argument[0] = foo1
argument[1] = foo2
argument[2] = foo3


Regards,
Rok

[Somnath Mallick]

In JAVA the common terminology of what you call "Functions" are known as "Methods".

You can try doing this:

a.abc( args[0], args[1], args[2]....)

Rok's example is a detailed one, because it handles the null value situation as well.

[shirish katti]

Give command as: java className 10 20 30 40

These are interpreted by compiler as :

args[0]=10
args[1]=20
args[2]=30
args[3]=40

Therefore
a.abc(10,20,30...)
These 10,20,30 are command line arguments..

[Campbell Ritchie]

shirish katti wrote:Give command as: java className 10 20 30 40

These are interpreted by compiler as :

args[0]=10 . . .

[pedantic mode]
They are interpreted by the JVM as . . . Not the compiler, which "knows" nothing about them.

args[0]="10" not 10. It is a String, hence the "".
[/pedantic mode]

[shirish katti]

yes campbell i was just giving a overview we need to parse them if we need to convert them to a integer as Integer.ParseInt(args[0])

I concentrated only on passing command line arguments..

[shirish katti]

Campbell:
[pedantic mode]
They are interpreted by the JVM as . . . Not the compiler, which "knows" nothing about them.

args[0]="10" not 10. It is a String, hence the "".
[/pedantic mode]



Obviously it is going to be interpreted as a string..

As the command line arguments are going to be array of strings..