Unable to rename file

[Siddhesh Khedekar]

Hi Experts,

I am tryin following code -

import java.io.*;
public class simple {
	public static void main(String[] args) {
		//Obtain the reference of the existing file
		File oldFile = new File("D:\\test\\Results.dat"); 
		System.out.println(oldFile.getName());
		//Now invoke the renameTo() method on the reference, oldFile in this case
		File f = new File(oldFile.getAbsolutePath());		
		f.renameTo(new File("D:\\test\\Results_May.dat"));
		System.out.println(f.getName());
	}
}

The folder D:\test already exists.
but not able to rename the file and getting output

Results.dat
Results.dat

[Rob Spoor]

File.renameTo does not change the File object. If it returns true it renames the file, yes, but the File object is immutable and stays exactly the same. Instead of using the old value of f you should reassign it:

import java.io.*;   
public class simple {   
    public static void main(String[] args) {   
        //Obtain the reference of the existing file   
        File oldFile = new File("D:\\test\\Results.dat");    
        System.out.println(oldFile.getName());   
        //Now invoke the renameTo() method on the reference, oldFile in this case   
        // since oldFile is immutable, no need to create a new File
        File f = oldFile;
        File newFile = new File("D:\\test\\Results_May.dat");
        if (f.renameTo(newFile))
        {
            // rename succeeded
            f = newFile;
        }
        System.out.println(f.getName());   
    }   
}