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How to pass a string constant as it is in powershell

I have the following simple java program:
import java.util.Arrays;
public class Arguments
{
public static void main(String [] args)
{
System.out.println("args: "+Arrays.toString(args));
}
}
When I execute this in powershell using the following command: java Arguments "*.java" the string received in the program is not "*.java" but a comma-separated list of all java files in the current directory. And if there are no java files in the current directory the string received is "*.java".
I want to know why this is happening and how to pass a string as it is without converting it.
Update: java Arguments '"*".java' and java Arguments `"*.java`" did the work but this creates the same problem when executed in cmd. Can anyone explain why this is happening? Is there any common solution for both PowerShell and cmd?

It is not PowerShell (nor cmd.exe) that interprets "*.java" as a filename pattern and expands (resolves) it to the matching files, known as globbing in the Unix world.
(You would only get that behavior if you used *.java - i.e., no quoting - in PowerShell Core on Unix-like platforms, but never with a quoted string such as "*.java" or '*.java', and even without quoting never on Windows).
Apparently, it is legacy versions of java.exe on Windows that automatically perform the globbing on unquoted arguments, in an apparent attempt to emulate the behavior of POSIX-like shells such as Bash on Unix.
As of (at least) JDK 12, this behavior no longer seems to be effect, at least not by default.
The linked answer suggests that in earlier versions there may be a system property that controls the behavior, but it's unclear what its name is.
Generally, the syntax java -D<systemPropName>=<value> ... can be used to set a system property on startup.
Therefore, you have the following options:
Upgrade to a Java version that no longer exhibits this behavior (by default).
In legacy versions, find the relevant system property name that disables the behavior and use the syntax shown above.
Use shell-specific quoting, as shown below.
Using quoting to prevent globbing:
To prevent java.exe from performing globbing, the invocation command line must ultimately contain "*.java", i.e., the argument must be enclosed in double quotes.
Unfortunately, there is no common syntax that works in both PowerShell and cmd.exe:
cmd.exe:
cmd.exe passes double-quoted arguments through as-is, so the following is sufficient:
java Arguments "*.java"
PowerShell:
PowerShell, by contrast, performs re-quoting as needed behind the scenes (see this answer for more information).
Since an argument with content *.java normally does not require quoting when you pass it to an external program, PowerShell translates both "*.java" and '*.java' to unquoted *.java in the command line that is ultimately used behind the scenes - which is what you experienced.
There are two ways around that:
Use java Arguments '"*.java"', i.e., embed the " chars. in the argument, inside a literal string ('...').
Use java Arguments --% "*.java"; --% is the stop-parsing symbol (PSv3+), which instructs PowerShell to pass the remainder of the command line through as-is (except for expanding cmd.exe-style environment-variable references).

Number and type of slashes in path in command prompt

This is kind of a ridiculous question but I am stucked with it and I need some help.
I am trying to install an open source software in my windows 8 system using command prompt. Everything is set correctly but when I type the final java command, to run the software, I get a series of exceptions.
I am sure that the problem is related with some slashes in the path. I know that the type and number of slashes is important and sometimes java requires this.
So I am not sure if I can get an answer about such a specific question here but I give it a try. This is the path I run in one line:
C:\Kuwaiba7\service>java -Djava.rmi.server.codebase="file:/C:/Kuwaiba7/service/lib/PersistenceAbstractionAPI.jar file:/C:/Kuwaiba7/Service/lib/PersistenceServiceRemoteInterfaces.jar" -jar PersistenceService.jar
I double/tripled checked the paths and tried different variations with the slashes but nothing gives me the expected result.
I get the following exceptions:
java.rmi.serverException
java.rmi.unmarshalException
java.lang.classNotFoundException
This is the format of the path they suggest in their manual but doesn't seem to work either:
Thanks
Dimitris

I found the solution and I post the answer here. Afterall the slashes were correct the way I had them. Although sometimes in Java the number and the type of the slashes counts that wasn't the case here.
What I did before was that I was starting the rmiregistry and then running the PersistenceService. That didn't work.
Then I tried to set the Classpath (from the directory where the PersistenceService.jar is located in my PC). After start the rmiregistry.exe (from the Java directory) and finally run the persistence service as shown above.
That made it work!

Command-line options working in windows, but not Linux

I have a .bat file on Windows/shell script on Linux that starts a large Java application from the command line. It configures the classpath, environment variables, etc.
At one point, it uses RMID to configure a bunch of services which will run in their own JVMs. The problem is that it won't allow me to specify multiple JARs for the codebase property on Linux. It's allowing me to do so on Windows just fine, but I think my syntax/styling must be wrong for the .sh script and am hoping a more experienced Linux user could have some tip. On Windows, the working line looks like this:
SET RMID_OPTIONS=%RMID_VM%
-J-DINSTALL_DIR=%CONFIG_PATH%
-C-DINSTALL_DIR=%CONFIG_PATH%
-J-DINSTALL_DIR_LOCAL=%HOME_DIR%
-C-DINSTALL_DIR_LOCAL=%HOME_DIR%
-J-Djava.security.policy=%PL_HOME%\windows\system.policy
-C-Djava.rmi.server.codebase=
"file:/%HOME_DIR%\jar1.jar file:/%HOME_DIR%\jar2.jar"
-J-Djava.rmi.server.codebase=
"file:/%HOME_DIR%\jar1.jar file:/%HOME_DIR%\jar2.jar"
// more stuff here
The only important lines are the ones setting the rmi.server.codebase property. The above works 100% fine, however, when trying to set multiple JARs in the codebase in Linux, it causes a general failure and the whole RMID command is not executed. My shell script looks like the following:
export RMID_OPTIONS="${RMID_VM}
-J-DINSTALL_DIR=${CONFIG_PATH}
-C-DINSTALL_DIR=${CONFIG_PATH}
-J-DINSTALL_DIR_LOCAL=${HOME_DIR}
-C-DINSTALL_DIR_LOCAL=${HOME_DIR}
-J-Djava.security.policy=${PL_HOME}/linux/system.policy
-C-Djava.rmi.server.codebase=
""file:/${HOME_DIR}/jar1.jar file:/${PL_HOME_LOCAL}/jar2.jar""
-J-Djava.rmi.server.codebase=
""file:/${HOME_DIR}/jar1.jar file:/${PL_HOME_LOCAL}/jar2.jar""
// more stuff here
"
The shell script itself works perfectly fine if only one JAR is specified, but any more and I get a general failure. Any suggestions on what I'm doing wrong? I'm open to try new things to fix this as all my attempts so far have been fruitless.

Under Linux, escaping quotes is done differently. You are attempting to use the Windows specific syntax, which will result in the jar files being passed as separate arguments, instead of a single one, as it should be.
Instead of "" to produce a quote inside quotes, you have to use \" in Linux:
export RMID_OPTIONS="... -C-Djava.rmi.server.codebase=\"file:/${HOME_DIR}/jar1.jar file:/${PL_HOME_LOCAL}/jar2.jar\" ..."
Aside from that, I'm not sure that the file:/ syntax is correct. It's probably either file:// or the absolute file path without anything preceding it, but you'll have to try it out.

You're doing this wrong. You don't need to start rmid with arguments and system properties at all. All that stuff should be specified when you register the ActivationGroup(s) you're going to use, in your activation setup program. That in turn means that all command-line problems should just disappear.

Java path problems on Cygwin

I'm trying to compile a Java project under Cygwin using a native Win32 Java.
The Java binaries are correctly found under /cygdrive/c/jdk/bin on my machine.
The following command works fine:
javac -d . ./gnu/kawa/util/PreProcess.java
The PreProcess.class file is generated in ./gnu/kawa/util/. Trying to invoke Java on this fails however:
CLASSPATH=.:$CLASSPATH java gnu.kawa.util.PreProcess \
%java6 +use:com.sun.net.httpserver +enable:XML \
`sed -e 's|\([^ ]*\)|./\1|' < ./patch-source-list`
Error: Could not find or load main class gnu.kawa.util.PreProcess
...
This command was invoked by make, that's where the $CLASSPATH variable is set dynamically. patch-source-list is just a list of class names. The : in the classpath looks suspicious, but I'm not sure how to test ; while not annoying sh.
My only other suspicion is that the native Java is trying gnu\kawa\util\PreProcess, but I think cygwin can transparently handle that.
Any ideas? Thanks for your time.

Another option would be to build your path using the ':' and then fix the results using cygpath. This is probably overkill in your specific situation, but in a general case where you may have references to multiple directories, some of which may be referenced as absolute rather than relative paths, or if you are working with cygwin symlinks, it is much more useful.
$ ln -s /cygdrive/c/development/libraries/ ../libs
$ cygpath -pw /cygdrive/c/development/:.:../libs
C:\development\;.;C:\development\libraries\
so then you'd build your CLASSPATH variable as before, and in the final stage run
CLASSPATH="`cygpath -pw "$CLASSPATH"`" java (whatever)

Remember, the JVM has no idea that you are using the cygwin bash shell.
Two things:
for the classpath locations, use the windows path names. Thus, no "/cygdrive/c/somepath", but "c:\somepath\" ("/" and "\" can be used interchangeably however)
use ';' instead of ':' in the classpath list
This should work:
export CLASSPATH="./gnu/kawa/util/PreProcess.class"
CLASSPATH=".;$CLASSPATH" java gnu.kawa.util.PreProcess

The : in the classpath looks suspicious, but I'm not sure how to test ; while not annoying sh.
You're exactly right: you need to use ; instead of :. As for how to use it — as Mat alludes to above, you need to "quote" the semicolon. Any of these will work:
CLASSPATH=.\;$CLASSPATH java Foo
CLASSPATH=.';'$CLASSPATH java Foo
CLASSPATH='.;'$CLASSPATH java Foo
CLASSPATH=".;$CLASSPATH" java Foo
You can use whichever one you like best. (The first uses a backslash, which quotes a single following character. The second and third use single-quotes, which quote a sequence of zero or more characters. The fourth uses double-quotes, which are like single-quotes except that they still allow the variable $CLASSPATH to be expanded. For that matter, you could also write something like
CLASSPATH=".;"$CLASSPATH java Foo
if you want. See the above link for lots more information about quoting in Bash.)

Strange error calling java program from python via command line

As part of my python-based program, I have to call a Java program - solved that perfectly with os.system(). It worked well, until I moved the entire thing from one directory to the other. I changed all the filepaths in the python code, and the java program - as best I can tell, I don't really understand java - relies on relative file paths, which weren't changed during the move. But now, the java program won't open. The command line appears then vanishes almost instantly, so I know that os.system() is working. It must be to do with the filepath I'm using in os.system, as when I change that back to the original filepath it works perfectly fine again. Code below:
os.system("java -jar C:\\Documents and Settings\\enginx_mgr.ISIS\\My Documents\\ISAProgramFiles\\JPivSource\\jpivc.jar %s"%fileNames)
Where fileNames is a variable thingie passed to the java program as an argument, which I'm fairly sure isn't the problem. If I call the python program directly from cmd.exe, then it gives me back the error message "Unable to access Jarfile C:\Documents". I thought this might have to do with the spaces in the filepath, so I put underscores in:
os.system("java -jar C:\\Documents_and_Settings\\enginx_mgr.ISIS\\My_Documents\\ISAProgramFiles\\JPivSource\\jpivc.jar %s"%fileNames)
And it gave me the same "Unable to access Jarfile" message, but this time with the full filepath. Trying os.path.exists() on the filepath returns true, so python knows its a real filepath; I guess it must be the command line disagreeing with it, but I don't know why. Any ideas?
Edit: Original filepath, if its of interest, was C:\Inetpub\ftproot\JPivSource\jpivc.jar
Edit 2: Its almost certainly not the filepath, going by the answers below and the fact that none of them work (and that the original filepath works). Checked the security options out of a hunch, and I have full control over the .jar file, as does the system, so its not that it can't access it for security reasons. Still at square zero.

Not a direct answer but ...
I think it is better to call .bat file instead of direct call to java with many command line option. This way you will not need to change Python program to add some other options (like -Xms2048m or -Dfile.encoding=utf8).
Such .bat file is also much easier to debug.

Your problem looks to be caused because of a typo somewhere. This should fix it:
Open Windows Explorer
right click on the file
click "Properties"
copy the location
paste that location into your script, with directories escaped.

You have to put quotes around your path.
os.system('java -jar "C:\\Documents and Settings\\enginx_mgr.ISIS\\My Documents\\ISAProgramFiles\\JPivSource\\jpivc.jar" %s' % fileNames)

I'm sorry for offering up another file path solution, but this wasn't mentioned, and it seems likely that the changing of paths would be causing the issue. So, if you wouldn't mind humouring me?
os.system("java -jar C:\\Documents\ and\ Settings\\enginx_mgr.ISIS\\My\ Documents\\ISAProgramFiles\\JPivSource\\jpivc.jar %s"%fileNames)
All I've done differently, is escape the spaces with a backslash.
You said that os.path.exists is returning True, and that's fine, but you're trying to execute a command line program by passing it a number of arguments. The program reading the arguments will interpret the string as several strings because of the spaces.
You could also try altering the quotes that you are using:
os.system('java -jar "C:\\Documents and Settings\\enginx_mgr.ISIS\\My Documents\\ISAProgramFiles\\JPivSource\\jpivc.jar" %s' % fileNames)
That file path you're using does look quite strange.