java: new File(“”, “name”) != new File(“name”) ? (file constructor with empty string)

Question

Noticed this today.

Given that a file named \"existing\" exists in the PWD of a java process (windows).

new File(\"existing\").exists() => true
         


        

Answer 1

I remember encountering this many moons ago, so I did some digging in the actual source. Here is the relevant source documentation from File.java:

/* Note: The two-argument File constructors do not interpret an empty
   parent abstract pathname as the current user directory.  An empty parent
   instead causes the child to be resolved against the system-dependent
   directory defined by the FileSystem.getDefaultParent method.  On Unix
   this default is "/", while on Microsoft Windows it is "\\".  This is required for
   compatibility with the original behavior of this class. */

So, the non-obvious behavior appears to be due to legacy reasons.