difference between toAbsolutePath() and toRealPath()

[Puspender Tanwar]

what is the difference between toAbsolutePath() and toRealPath() . Both returns exactlly the same path object .

Path p1= Paths.get("/io/newdir");
System.out.println(p1.toAbsolutePath());
System.out.println(p1.toRealPath());

both will give same output :
C:\io\newdir
C:\io\newdir

[Ahmed Bin S]

toRealPath() will resolve symbolic links.

So if C:\io was a symbolic link to D:\my_io, then toRealPath() would give D:\my_io\newdir.

Also, if the path+file doesn't actually exist, then toRealPath() throws an exception whereas toAbsolutePath() doesn't.

[Puspender Tanwar]

thanks Ahmed

[Scott Selikoff]

The most important distinction is that toRealPath() operates on actual file system records, whereas toAbsolutePath() is based on theory. For example, you can create a dozen Path objects that's do not exist, perform numerous operations in them such as relativize(), toAbsolutePath(), normalize(), etc. Once you call toRealPath(), though, the application will throw an exception if the Path does not exist.

[Dana Ucaed]

So,


My code don't throws any exception.

The path D://PrjJava//OCP71//..  don't exist.

package nio2_practice4;

import java.io.IOException;
import java.nio.file.Paths;

public class NIO2_Practice4 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws IOException {
        try
        {
        //System.out.println(Paths.get("D:/PrjJava/OCP71/..").normalize());
        System.out.println(Paths.get("D://PrjJava//OCP71//..").toRealPath());
        }
        catch(Exception ex)
        {
            ex.printStackTrace();
        }

    }

}

My question is : Where is the mistake?

Thanks in advance.

[Dave Tolls]

Does the PrjJava directory exist?
If so then toRealPath() won't throw an exception for "D:/PrjJava/OCP71/..".

[Dana Ucaed]

Finally, I understand the behavior:

import java.io.IOException;
import java.nio.file.Paths;

public class NIO2_Practice4 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws IOException {
        try
        {
        System.out.println(Paths.get("D:/PrjJava/OCP71/..").normalize());
        System.out.println(Paths.get("D://PrjJava//OCP71//..").toRealPath());
        System.out.println(Paths.get("D://PrjJava//OCP71").toRealPath()); // throws Exception
        
        }
        catch(Exception ex)
        {
            ex.printStackTrace();
        }

    }

}

The last statement throws java.nio.file.NoSuchFileException: D:\PrjJava\OCP71.

and the second statement returns D:\PrjJava.