Windows paths, Java, and command-line arguments, oh my!

S

Steve M

I'm trying to invoke a Java command-line program from my Python program
on Windows XP. I cannot get the paths in one of the arguments to work
right.

The instructions for the program describe the following for the
command-line arguments:

java -jar sforcedataloader.jar -Dsalesforce.config.dir=CONFIG_DIRECTORY

They also give an example:

java -Dsalesforce.config.dir=c:\config -jar sforcedataloader.jar

If I type the example above at the cmd.exe command line the thing works
(assuming I have the config file in c:\config). What doesn't work is
these two lines:

cmd = r'java -jar sforcedataloader.jar -Dc:\config'
os.system(cmd)

I have tried (not entirely systematically but pretty exhaustively)
every combination of backslashes in the cmd string, e.g.:
-Dc\:\\config
-Dc:\\config
-Dc\\:\config
-Dc\\:\\config
etc.

No matter what I do, the program outputs that it cannot find the config
file. I cannot tell whether this is a java thing (why are there three
different styles for argument on the same command line? In addition to
"-jar xxx" and "-Dxxx=yyy" you can also put "xxx=yyy" for some
options... wth?), Windows lame cmd.exe shell (is that program invoked
by Python's os.system function?), or something else that is messing up.
It drivin me crazy though. (Come to think of it, Windows paths have
been a persistent thorn in my side for two years of Python development
at my company.)

Anybody have any suggestions?

p.s. 1. I would like to qualify the claim above that the example works
at the command-line. I'm not completely certain exactly which form of
invocation was successful at the command line, but at least one of them
was and that one definitely didn't work from Python.
2. I have a work-around available to me, which is that the program will
look for the configuration file in the current directory if the
command-line option isn't specified. I'd much rather be able to specify
a directory on the command line, so that I can have multiple
simultaneous invocations, and so that I can have the configuration file
not be in the directory where the Python program is, or alternatively
not have to change my directory (since I don't fully appreciate the
implications for other parts of my program - this thing runs
asynchronously.)
 
R

Robert Kern

Steve said:
I'm trying to invoke a Java command-line program from my Python program
on Windows XP. I cannot get the paths in one of the arguments to work
right.

The instructions for the program describe the following for the
command-line arguments:

java -jar sforcedataloader.jar -Dsalesforce.config.dir=CONFIG_DIRECTORY

They also give an example:

java -Dsalesforce.config.dir=c:\config -jar sforcedataloader.jar

If I type the example above at the cmd.exe command line the thing works
(assuming I have the config file in c:\config). What doesn't work is
these two lines:

cmd = r'java -jar sforcedataloader.jar -Dc:\config'

That's not the same thing as the examples you give above. Namely, you're
missing the "salesforce.config.dir=" which is probably pretty
fundamental to telling the program where the salesforce config dir is.

--
Robert Kern
(e-mail address removed)

"In the fields of hell where the grass grows high
Are the graves of dreams allowed to die."
-- Richard Harter
 
D

Daniel Dittmar

Steve said:
I'm trying to invoke a Java command-line program from my Python program
on Windows XP. I cannot get the paths in one of the arguments to work
right.

The instructions for the program describe the following for the
command-line arguments:

java -jar sforcedataloader.jar -Dsalesforce.config.dir=CONFIG_DIRECTORY

They also give an example:

java -Dsalesforce.config.dir=c:\config -jar sforcedataloader.jar

If I type the example above at the cmd.exe command line the thing works
(assuming I have the config file in c:\config). What doesn't work is
these two lines:

cmd = r'java -jar sforcedataloader.jar -Dc:\config'
os.system(cmd)

If you write
java -jar x.jar -Dwhatever=x
then -Dwhatever=x is passed as an argument to the main method of the
main class in x.jar.

If you write
java -Dwhatever=x -jar x.jar
then -Dwhatever=x is interpreted by java and put into the system properties.

Daniel
 
S

Steve M

Well, apparently I fried my brain trying to sort this out. There is a
typo in my example code in the post but not in my real program. (I know
it is a no-no when asking help on c.l.py but I simplified some details
from the real code in order not to confuse the issues. Probably
backfired by this point.) Below is the post with the error fixed and
one sentence added (to clarify why the error in my original post really
was not the problem). Thanks for any advice.
---
I'm trying to invoke a Java command-line program from my Python program
on Windows XP. I cannot get the paths in one of the arguments to work
right.

The instructions for the program describe the following for the
command-line arguments:

java -jar sforcedataloader.jar -Dsalesforce.config.dir=CONFIG_DIRECTORY

They also give an example:

java -Dsalesforce.config.dir=c:\config -jar sforcedataloader.jar

If I type the example above at the cmd.exe command line the thing works
(assuming I have the config file in c:\config). What doesn't work is
these two lines:

cmd = r'java -jar sforcedataloader.jar
-Dsalesforce.config.dir=c:\config'
os.system(cmd)

I have tried (not entirely systematically but pretty exhaustively)
every combination of backslashes in the cmd string, e.g.:
-Dsalesforce.config.dir=c\:\\config
-Dsalesforce.config.dir=c:\\config
-Dsalesforce.config.dir=c\\:\config
-Dsalesforce.config.dir=c\\:\\config
etc.

No matter what I do, the program outputs that it cannot find the config
file.

*For at least one variation of the cmd string, I can print the value of
cmd and copy/paste it to the command line and the java program works
successfully, while for this same cmd string the java program fails
when invoked from Python.*

I cannot tell whether this is a java thing (why are there three
different styles for argument on the same command line? In addition to
"-jar xxx" and "-Dxxx=yyy" you can also put "xxx=yyy" for some
options... wth?), Windows lame cmd.exe shell (is that program invoked
by Python's os.system function?), or something else that is messing up.
It drivin me crazy though. (Come to think of it, Windows paths have
been a persistent thorn in my side for two years of Python development
at my company.)

Anybody have any suggestions?

p.s. 1. I would like to qualify the claim above that the example works
at the command-line. I'm not completely certain exactly which form of
invocation was successful at the command line, but at least one of them
was and that one definitely didn't work from Python.
2. I have a work-around available to me, which is that the program will
look for the configuration file in the current directory if the
command-line option isn't specified. I'd much rather be able to specify
a directory on the command line, so that I can have multiple
simultaneous invocations, and so that I can have the configuration file
not be in the directory where the Python program is, or alternatively
not have to change my directory (since I don't fully appreciate the
implications for other parts of my program - this thing runs
asynchronously.)
 
D

Daniel Dittmar

Steve M wrote:

About your main problem: I'm still convinced that it's the order of -jar
and -D that is important, see my other post.
I have tried (not entirely systematically but pretty exhaustively)
every combination of backslashes in the cmd string, e.g.:
-Dsalesforce.config.dir=c\:\\config
-Dsalesforce.config.dir=c:\\config
-Dsalesforce.config.dir=c\\:\config
-Dsalesforce.config.dir=c\\:\\config
etc.

A hint:
- if you're unsure how something must be entered as a literal, test it
in the interactive interpreter:
enter a path: c:\config
'c:\\config'

Daniel
 
N

Neil Benn

Steve said:
Well, apparently I fried my brain trying to sort this out. There is a
typo in my example code in the post but not in my real program. (I know
it is a no-no when asking help on c.l.py but I simplified some details
from the real code in order not to confuse the issues. Probably
backfired by this point.) Below is the post with the error fixed and
one sentence added (to clarify why the error in my original post really
was not the problem). Thanks for any advice.
---
I'm trying to invoke a Java command-line program from my Python program
on Windows XP. I cannot get the paths in one of the arguments to work
right.

The instructions for the program describe the following for the
command-line arguments:

java -jar sforcedataloader.jar -Dsalesforce.config.dir=CONFIG_DIRECTORY

They also give an example:

java -Dsalesforce.config.dir=c:\config -jar sforcedataloader.jar

If I type the example above at the cmd.exe command line the thing works
(assuming I have the config file in c:\config). What doesn't work is
these two lines:

cmd = r'java -jar sforcedataloader.jar
-Dsalesforce.config.dir=c:\config'
os.system(cmd)

<snip>
Unless you have fixed your typo in a different place, you have the same
problem as before. There are two issues, you need to escape the
backslash and you have the java properties line in the wrong place.
Instead of:

cmd = r'java -jar sforcedataloader.jar -Dsalesforce.config.dir=c:\config'
os.system(cmd)

use

cmd = r'java -Dsalesforce.config.dir=c:\\config -jar sforcedataloader.jar'
os.system(cmd)

Neil

--

Neil Benn
Senior Automation Engineer
Cenix BioScience
BioInnovations Zentrum
Tatzberg 47
D-01307
Dresden
Germany

Tel : +49 (0)351 4173 154
e-mail : (e-mail address removed)
Cenix Website : http://www.cenix-bioscience.com
 
N

Neil Benn

Neil said:
Steve M wrote:



Unless you have fixed your typo in a different place, you have the same
problem as before. There are two issues, you need to escape the
backslash and you have the java properties line in the wrong place.
Instead of:

cmd = r'java -jar sforcedataloader.jar -Dsalesforce.config.dir=c:\config'
os.system(cmd)

use

cmd = r'java -Dsalesforce.config.dir=c:\\config -jar sforcedataloader.jar'
os.system(cmd)

Neil
Whoops you are using a raw string - you only need one backslash - the
java thing is still the same though

Cheers,

Neil
 
S

Steve M

Thank you. I was able to fix it by putting the '-Dwhatever=x' bit
before the '-jar y.jar' bit. I had no idea this could matter.
Thanks all for the help.
 

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