File("") broken in 1.4.1_02 ?

Question

hi,
running the code below for 1.4.1_02 gives this output
H:\java\misc\forums>java CurDir
H:\java\misc\forums exists? false
H:\java\misc\forums exists? true
H:\java\misc\forums>java -version
java version "1.4.1_02"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_02-b06)
Java HotSpot(TM) Client VM (build 1.4.1_02-b06, mixed mode)
which I think works with earlier runtimes? is this a new bug!?
thanks,
asjf
import java.io.*;
public class CurDir
     public static void main(String [] arg) {
          File curdir = new File("");
          System.out.println(curdir.getAbsolutePath() + " exists? " + curdir.exists());
          curdir = new File(curdir.getAbsolutePath());
          System.out.println(curdir.getAbsolutePath() + " exists? " + curdir.exists());
}

Answer 1

H:\java\misc\forums>java CurDir
H:\java\misc\forums exists? false
H:\java\misc\forums exists? true
public class CurDir
     public static void main(String [] arg) {
          File curdir = new File("");
          curdir = new File(curdir.getAbsolutePath());
}I think what may be happening here is that, in the first case, you are selecting a file named "" in the current directory (not the directory itself). The absolute path name of this is then given as a string: "H:\java\misc\forums\" + "" (directory + file name). However, this string (when concatenated) represents a directory in the second case. That is, the second one is the current directory, while the first one is a file "" in the current directory ("" would not be a valid file). Internally, File contains a name sequence, representing the hierarchy of directory and file names. My guess is that in one case the hierarchy is {"H:", "java", "misc", "forums", ""} and the other {"H:", "java", "misc", "forums"}; see the difference?
You can test this out using File.getName() or File.getParent() to see if they represent different things:
File firstFile = new File("");
File secondFile = new File(firstFile.getAbsolutePath());
System.out.println("Name of first file:    " + firstFile.getName());
System.out.println("Name of second file:   " + secondFile.getName());
System.out.println("Parent of first file:  " + firstFile.getParent());
System.out.println("Parent of second file: " + firstFile.getParent());If you are looking to get the current directory, you may want to use "." instead of "". Alternatively, you can get the current working directory from the system properties.