Re: [DrJava] RE: Current Directory Debate

[Charles R. <creis@u.washington.edu>]

   Unfortunately, we've investigated this before, and that approach only=20
works the first time you change the "user.dir" property.  It's also=20
explicitly (purposely) undocumented in the JVM specs, so there are=20
likely JVMs that do not implement this behavior.  (I haven't tried it on=20
Apple's JVM.)  There are many discussions about the issue on=20
groups.google.com and the Java forums, but it boils down to the fact=20
that this approach isn't reliable or recommended...

Charlie


Jonathan Lugo wrote:
> In terms of implementation, I believe it is quite easy to=20
> programmatically change the default abstract path used by most file IO.=
 =20
> The java.io.File class uses the System property, =93user.dir=94 when=20
> determining the file=92s absolute path.  This property is easily change=
d=20
> by using the following code:
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> =20
>=20
> System.setProperty(=93user.dir=94, =93<<default directory>>=94);.
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> =20
>=20
> I ran the following code in the interactions pane and it successfully=20
> changed the output of the getAbsolutePath() method of a java.io.File=20
> object.  It also worked on java=92s XML parser.  If this system change=20
> could be made in the interactions pane, could it be done as easily=20
> behind the scenes by drjava?  We could have some sort of code that=20
> chooses a good default based on the open/selected files that can be=20
> overruled by the user easily.  There could be a =93change current worki=
ng=20
> directory=94 button on the interactions pane.  This concept could also =
be=20
> applied to Unit testing just incase.
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> =20
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> I admit that I have not thoroughly researched the repercussions of=20
> changing this system property, but I know the change lasted only until =
I=20
> reset the interactions pane again.
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> =20
>=20
> - Jonathan Lugo
>=20