hi,

i have written a java program and i am able to compile the program by

javac myprog.java

and then i can run the program by

java myprog

what i want to know is whether it is possible in linux to convert this class or the java program into an executable program ,so that i needn't type

java myprog

everytime i have to run the program..i mean for example
by typing

$./myprog

i should be able to run my program....
someone told me that in windOS by converting it to jar file it can be run without any command..i tried that in linux by converting it to a jar. but then it says it's an archive...:-)).

somebody pls help me...

The latest version of gcc has the abaility to make native binaries from java (using gcj) but I haven't had much success with it.

tell me where i can get gcj ,?

thanx.

Its part of the latest gcc... which is at gnu.org

you MUST run the java virtual machine when running the java program, but there are a few things you can do to make an executable.

first, just make a script file in it, put java filename.java then make the scirpt executable, this will do the trick for you in linux. also, if you are really bored, you can make a c progam that just runs a system call to run the file. i would look like

#include <stdlib.h>

int main(){

system("java filename.java");
return 1;
}

just compile this (using gcc -o COMMANDNAME file.c)
where the commandname is the command you want to call (basically the executable) and the file.c is the name of the file.
this will only work if the java path is set up right on the machine.

for winblows, you can create a .bat file that just has java filename.java in it. you MAY be able to to run the above c program too, but i am not so sure about the win api.

if you want to create a jar file, in windows, just zip the file and rename it to jar, its the same thing. then you can double click it and it will run, but you have to name the jar the same as the class with the main thread.

Not quite true. Native compilers do exist. You only need the JVM to run bytecode.

let's froget windOS........
so if i use this C pgm to run the java pgm won't the $CLASSPATH make problems.......!

thanx

The C program was an "if you are really bored", you can just use a shell script.

/usr/local/bin/myprog:
(where /path/to/myprog is the class file without the extension).

... and $CLASSPATH isn't an issue becuase it doesn't change just becuase you run a shell script (or C program) AFAIK.

Ooh hang on, how about compiling the program and then typing:

%chmod x + g myprog.class

then you should be able to run it like:

%./myprog

No, Java class files are bytecode and not ELF or a.out executables. Linux can't just execute them.

Yeah, sorry, it's only applets that can use that.

Ummm... no.

Applets are even tricker to get going then applications.

You need to create a webpage with the applet in it, then load the webpage in a java capable web browser or appletviewer.

Dorwardi, with all respect:

$javac MyStandaloneWhatever.java
$chmod +x MyStandaloneWhatever.class
$./StandaloneWhatever.class

will work unless you have have less than kernel version 2.0

It's always a good idea to try these things out first

You're forgiven for thinking it might not work because according to 'Running Linux' by O'Reilly, IBM and Microsoft can't figure it out either.

david@cyberman:Assignment5]javac in2post.java
david@cyberman:Assignment5]chmod +x in2post.class
david@cyberman:Assignment5]./in2post.class
bash: ./in2post.class: cannot execute binary file
david@cyberman:Assignment5]uname -a
Linux cyberman 2.4.15-greased-turkey #1 Sat Nov 24 19:20:45 GMT 2001 i686 unknown
david@cyberman:Assignment5]

Not being a java expert, far from it, I didn't think you could simply execute a class file from the shell. I always thought that you need the interpreter.

Just thought I'd add.