I just want to be able to do ./whatever.jar instead of java -jar whatever.jar.
I've found a way:
#!/bin/bash
java -jar $0 $*
exit
# jar goes here...
but it doesn't work. Java just complains that it's an invalid/corrupt jarfile.
I also tried piping:
#!/bin/bash
tail -n +4 $0 | java -jar
exit
# jar goes here...
but this doesn't work.
One way to do it is to somehow split the file into two separate parts (the script part and the jar part), and then execute the jar, but that'd be redundant. You'd might as well make a script that executes the jar and execute that script.
So I need to figure out how to somehow tail it and fake the file.
I thought I could do it using /dev/stdout:
#!/bin/bash
java -jar /dev/stdout
tail -n +5 $0
exit
# jar goes here...
That doesn't work either. It just prints the contents of the jar and java complains that it's invalid. (I figured out later that there's nothing to read in /dev/stdout)
So I need to read from stdout some other way. I really wish I could pipe it though. It would make things SO much easier :)
You need a service called jexec some linux distros come with this installed check for /etc/init.d/jexec. My CentOS 5.5 definitely does.
What it does is register the jexec interpreter with the binfmt system.
For more information you might what to have a quick read of binfmt_misc.
Assuming you have the kernel source code installed, check out /usr/src/linux/Documentation/java.txt for a way to run Java code directly using the kernel's BINFMT_MISC support (assuming it's compiled into the version of the kernel you're running, but I think it is on most major distros). If you don't have the source installed, you should be able to find it online easy enough (here's one example).
FYI, if you wanted to do it your original way it would go like this:
$ cat jar.sh
#!/usr/bin/env bash
java -jar <(tail -n +4 "$0")
exit
$ cat jar.sh runme.jar > works.jar
$ chmod a+x works.jar
$ ./works.jar
Presuming a recent bash with support for <()
java -jar does not work with stdin, apparently it does some seeks rather than straight reads.
On a system you can't mod, you have to use a tmp. for example.
#!/bin/bash
JF=/tmp/junk$$.jar
(uudecode -o /dev/stdout >$JF;java -jar $JF;unlink $JF) <<JAR
begin-base64 644 junk.jar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====
JAR
Or I could just install the jarwrapper (Ubuntu) package.
Write a separate shell script:
whatever.sh
#!/bin/bash
java -jar whatever.jar $*
You can't make the JAR file directly executable because it's not an executable file. It's Java bytecode which can't be read directly by the machine nor any standard shell interpreter that I know of.
Related
This is my exact batch file. I have tried to convert it doing some research online and get an error
"Failed to execute child process "/home/pi/Desktop/TeachVal/TeachValLinuxShell" (No such file or directory)
echo off
cls
echo Running TeachVAL II...
set path=%path%;/Library/Java/JavaVirtualMachines/jdk1.8.0_65.jdk/Contents/Home/bin
java -classpath comm.jar;Robot.jar;TeachVAL TeachVAL
cls
exit
This one is my attempt at translating.
#!/bin/bash
set +v
clear
echo "Running TeachVAL II..."
java -cp ".dir1;dir2;path/home/pi/Desktop/TeachVAL/comm.jar;
path/home/pi/Desktop/TeachVAL/Robot.jar;/home/pi/Desktop/TeachVAL/TeachVAL"
clear
exit
Welcome to Linux--life is good here, but there are a few things that work slightly differently, when compared to Windows.
One difference is that Windows uses semicolon (;) to separate entries in a list of paths, but Linux uses colons (:) for that purpose.
So, the Windows command:
java -classpath comm.jar;Robot.jar;TeachVAL TeachVAL
would correspond to this on Linux:
java -classpath comm.jar:Robot.jar:TeachVAL TeachVAL
In general, on Linux, semicolons are used to put multiple command lines into a single line. Once you've learned that, I think you can then understand why:
java -cp .dir1;/home/pi/Desktop/TeachVAL/TeachVAL
would be the same as:
java -cp .dir1
/home/pi/Desktop/TeachVAL/TeachVAL
That would run java (with no class to be executed) and then try to run "/home/pi/Desktop/TeachVAL/TeachVAL" which can't be found.
There are many more differences to learn; here's a page that will help you get started: http://tldp.org/LDP/abs/html/dosbatch.html
I have written a Java application that analyzes my phone bills and calculates the average. At the moment I execute it like:
$ java -jar analyze.jar bill_1.pdf bill_2.pdf
But I want to install the application to my system. So I can just fire up a terminal type in the name of the application and the arguments and hit enter. Like any other "normal" program.
$ analyze bill_1.pdf bill_2.pdf bill_3.pdf
I know I can write a shell script and install it to "/usr/bin/" but I can't believe that there is no "native" way.
So please help, sorry for dump question.
Thank's in advance
One neat little trick is that you can append a basic shell script to the start of the jar file which will run it appropriately. See here for the full example but the basics are:
stub.sh
#!/bin/sh
MYSELF=`which "$0" 2>/dev/null`
[ $? -gt 0 -a -f "$0" ] && MYSELF="./$0"
java=java
if test -n "$JAVA_HOME"; then
java="$JAVA_HOME/bin/java"
fi
exec "$java" $java_args -jar $MYSELF "$#"
exit 1
Then do...
cat stub.sh helloworld.jar > hello.run && chmod +x helloworld.run
And you should be all set! Now you can just call the script-ified jar directly.
./helloworld.run
What you did so far is basically "the native" way.
You have to keep in mind: Java applications are compiled to byte code. There simply is no binary for your application that you could invoke. You do need this detour of calling some JVM installation with a pointer to the main class you want to run. In owhther words; that is what the vast majority of java applications are doing.
Theoretically, there are products out that there that you could use to actually create a "true" binary from your application; but that isn't an easy path (see here for first starters); and given your statement that your just looking for more "convenience" it is definitely inappropriate here.
I'm writing an application that leverages jsvc to start up a Java service as a daemon. I need to use something like jsvc because my application utilizes ports under 1024 and yet I'd really like to not run it as root so that created files are owned by another user. I'd also like to keep dependencies and configuration to a minimum so that all the client needs is a JVM and the jsvc binary installed.
However, it seems that jsvc has one major catch; it can't detect the home folder of Java on a given Unix operating system, which is quite frustrating:
$ ./startup.sh
Cannot locate Java home
I have been able to work around the issue on Ubuntu at least by manually setting the JVM home directory:
jsvc ... -home /usr/lib/jvm/default-java/ ...
Is there any way to determine the Java home directory dynamically from a Bash script so I can make this work across most Unixes/Linuxes? I'd be able to sleep much better at night doing something like:
JAVA_HOME="$( ... )"
jsvc ... -home "$JAVA_HOME" ...
...rather than hard-coding for each individual operating system. Is there a way that, given a java binary, I can find the home directory of its JVM/JRE?
Not sure if this works across *nixes, but found this solution:
JAVA_HOME="$( readlink -f "$( which java )" | sed "s:bin/.*$::" )"
I've tested it on Ubuntu and it works, however it does not work for OSX.
My solution was compiling the native linux source as the main jsvc page says in
http://commons.apache.org/proper/commons-daemon//jsvc.html
Here is my step by step procedure
Download www.fightrice.com/mirrors/apache/commons/daemon/source/commons-daemon-1.0.13-src.tar.gz
Once you extract the file then go to ...../commons-daemon-1.0.13-src/src/native/unix
in terminal as a root do the following:
$ support/buildconf.sh
$ ./configure --with-java=/usr/lib/jvm/default-java
$ make
test generated jsvc binary app
$ ./jsvc -help
It works! cleanly.
Use dirname and which commands to find Java's bin directory:
echo `dirname \`which java\``
JAVA_HOME=`dirname \`which java\``
... Only works if Java is already on the $PATH.
One other way is :
type -p java
Expect this to return the correct JAVA installation folder.
First, I already googled but only found examples where a compressed file (say a .tar.gz) is embedded into a shell script.
Basically if I have a C program (hello.c) that prints a string, say Hello World!.
I compile it to get an executable binary
gcc hello.c -o hello
Now I have a shell script testEmbed.sh
What I am asking is if it is possible to embed the binary (hello) inside the shell script so that when I run
./testEmbed.sh
it executes the binary to print Hello World!.
Clarification:
One alternative is that I compress the executable into an archive and then extract it when the script runs. What I am asking is if it is possible to run the program without that.
Up until now, I was trying the method here. But it does not work for me. I guess the author was using some other distribution on another architecture. So, basically this did not work for me. :P
Also, if the workflow for a C program differs from a Java jar, I would like to know that too!
Yes, this can be done. It's actually quite similar in concept to your linked article. The trick is to use uuencode to encode the binary into text format then tack it on to the end of your script.
Your script is then written in such a way that it runs uudecode on itself to create a binary file, change the permissions then execute it.
uuencode and uudecode were originally created for shifting binary content around on the precursor to the internet, which didn't handles binary information that well. The conversion into text means that it can be shipped as a shell script as well. If, for some reason your distribution complains when you try to run uuencode, it probably means you have to install it. For example, on Debian Squeeze:
sudo aptitude install sharutils
will get the relevant executables for you. Here's the process I went through. First create and compile your C program hello.c:
pax> cat hello.c
#include <stdio.h>
int main (void) {
printf ("Hello\n");
return 0;
}
pax> gcc -o hello hello.c
Then create a shell script testEmbed.sh, which will decode itself:
pax> cat testEmbed.sh
#!/bin/bash
rm -f hello
uudecode $0
./hello
rm -f hello
exit
The first rm statement demonstrates that the hello executable is being created anew by this script, not left hanging around from your compilation. Since you need the payload in the file as well, attach the encoded executable to the end of it:
pax> uuencode hello hello >>testEmbed.sh
Afterwards, when you execute the script testEmbed.sh, it extracts the executable and runs it.
The reason this works is because uudecode looks for certain marker lines in its input (begin and end) which are put there by uuencode, so it only tries to decode the encoded program, not the entire script:
pax> cat testEmbed.sh
#!/bin/bash
rm -f hello
uudecode $0
./hello
rm -f hello
exit
begin 755 hello
M?T5,1#$!`0````````````(``P`!````$(,$"#0```#`!#```````#0`(``'
M`"#`'#`;``8````T````-(`$"#2`!`C#````X`````4````$`````P```!0!
: : :
M:&%N9&QE`%]?1%1/4E]%3D1?7P!?7VQI8F-?8W-U7VEN:70`7U]B<W-?<W1A
M<G0`7V5N9`!P=71S0$!'3$E"0U\R+C``7V5D871A`%]?:38X-BYG971?<&-?
4=&AU;FLN8G#`;6%I;#!?:6YI=```
`
end
There are other things you should probably worry about, such as the possibility that your program may require shared libraries that don't exist on the target system, but the process above is basically what you need.
The process for a JAR file is very similar, except that the way you run it is different. It's still a single file but you need to replace the line:
./hello
with something capable of running JAR files, such as:
java -jar hello.jar
I think makeself is what you're describing.
The portable way to do this is with the printf command and octal escapes:
printf '\001\002\003'
to print bytes 1, 2, and 3. Since you probably don't want to write that all by hand, the od -b command can be used to generate an octal dump of the file, then you can use a sed script to strip off the junk and put the right backslashes in place.
My java program was written on a windows machine and I am trying to get it installed and running on a Ubuntu 10.04 machine. I have created a .tar.gz file with myProgram.jar in it as well as 5 supporting library .jar files in a lib folder. Where do I put these files? Do I need to extract it on the Linux machine to a usr/bin folder? Does the shell script go inside the tar.gz? I have read that if you write the shell script on a windows machine you can have issues once you move it to the Linux machine, so I am writing the shell script on the Linux machine using gedit. I am just not sure what to do next.
So far in my script I have,
#!/bin/bash
java -jar myProgram.jar
I am going to try and extract the tar.gz file to the usr/bin directory and see if it runs.
Any suggestions or help would be greatly appreciated.
Thanks in advance,
Ray
Your question is quite "broad" :). I hope you find the following useful.
Do not extract the files to /usr/bin. See e.g. http://en.wikipedia.org/wiki/Filesystem_Hierarchy_Standard on where and where not to put files on a *nix system.
Extract the jar's to e.g. /opt/yourProgram/*.
The shell script should be inside there too. Make sure its executable (i.e chmod 755 script.sh)
In your shell script add cd /opt/yourProgram to have the proper working directory for your program before you invoke java.
If you want this program to be started easily by everyone create a symbolic link in /usr/bin or better in /usr/local/bin pointing to your script. Do this as last step after everything else is working.
In your shell script you'll have to add the other jars to the classpath e.g.
java -cp lib/some.jar:lib/other.jar -jar myProgram.jar
or
java -cp lib/some.jar:lib/other.jar:myProgram.jar com.acme.ClassContainingMain
Recommended practice: Add set -e at the very beginning of your script
As you already mentioned it's considered harmful to edit a shell script using a windows editor. The reason is that the windows editor will encode line-breaks (i.e. you hit the Return key) differently. This will make bash puke :)
Im not too clear of what you are looking for.
The script that you have written should work absolutely fine if you have placed your script and myprogram.jar at the same level.
And also im not sure how your myprogram.jar is referring the dependent libraries. So can't comment on them. Best bet will be to place your script and all jars together and try running the script.