renameTo()

[Prateek Rawal]

K & B P.No: 456 states that:

you must give valid new File object with the new name you want. If the new file object is null, NullPointerException will be thrown

Consider the code:

 import java.io.*;
class Now {
public static void main(String[] args){
try {
File f = new File("name");
f.mkdir();
File f1 = null;
f.renameTo(f1);

}
catch(Exception e){}


}

}   

Line 01 must throw NPE but it doesn't.....a new directory with name "name" is created in the current directory and the programs compiles and runs successfully....
What should i conclude?

[Abimaran Kugathasan]

How do you tell, that the program doesn't give Exception, you should check it. Try the below code..

 import java.io.*;
public class Now {
	public static void main(String[] args){
		try {
			File f = new File("name");
			f.mkdir();
			File f1 = null;
			System.out.println(f.renameTo(f1));
			System.out.println("OK");

		}	catch(Exception e){
			e.printStackTrace();}


	}

}

[Prateek Rawal]

I'm really sorry for the question, i asked a silly query...

Anyway thanks Abimaran

PS: I hope i referred you right this time

[Abimaran Kugathasan]

Prateek Rawal wrote:
Anyway thanks Abimaran
PS: I hope i referred you right this time

Welcome!