Scanner Example from K&B.

[aruna dabas]

dear Friends Please Explain me this code.

import java.util.Scanner;
public class ScanNext{
public static void main(String args[]){
boolean b2,b;
int i;
String s,hits=" ";
Scanner s1=new Scanner(args[0]);
Scanner s2=new Scanner(args[0]);
while(b=s1.hasNext()){
s=s1.next();
hits += "s";
}
while(b=s2.hasNext()){
if(s2.hasNextInt()){
i=s2.nextInt();
hits+="i";
}else if(s2.hasNextBoolean()){
b2=s2.nextBoolean();
hits +="b";
}else{
s2.next();hits +="s2";}
}
System.out.println("hits" +hits);
}
}

if this program is invoked with
% java ScanNext "1 true 34 hi"

it produces
hits ssssibis2

THANK YOU.

[Wouter Oet]

I have modified the code a bit. Now you must be able to figure it out yourself.

package testproject;

import java.util.Scanner;

public class ScanNext
{

	public static void main(String args[])
	{
		boolean b2, b;
		int i;
		String s, hits = " ";
		Scanner s1 = new Scanner(args[0]);
		Scanner s2 = new Scanner(args[0]);

		System.out.println("Args: " + args[0]);

		while(b = s1.hasNext())
		{
			s = s1.next();
			System.out.println("While 1: " + s);
			hits += "s";
		}
		while(b = s2.hasNext())
		{
			if(s2.hasNextInt())
			{
				i = s2.nextInt();
				System.out.println("While 2 case 1: " + i);
				hits += "i";
			} else if(s2.hasNextBoolean())
			{
				b2 = s2.nextBoolean();
				System.out.println("While 2 case 2: " + b2);
				hits += "b";
			} else
			{
				String st = s2.next();
				System.out.println("While 2 case 3: " + st);
				hits += "s2";
			}
		}
		System.out.println("hits"+hits);
	}

}

Good luck,
Wouter Oet

[Wouter Oet]

I forgot:

Please note that there is a difference between

java ScanNext "1 true 34 hi"
java ScanNext 1 true 34 hi

Good luck,
Wouter Oet

[kshitij dogra]

well thats a bit simple aruna

In the first while loop the default delemiter is 'space'. So as comes new literals may they be boolean, int etc. 's' is being concatenated

In the second while; again the defalut delimeter is space, but here you are being precise , as you are distinguishing between
-integer
-boolean
-others