Develop Reference

Translation of java commands in Linux systems

I am currently using a linux system to execute a specific command that translates into another java command (java - jar)
For example:
when i try execute /usr/bin/a in terminal, it will read the /usr/bin/a command and translates into 'java -jar' command
I do not want to execute 'java -jar' command directly and i would to specify a full path in executing the command so is there a possible way to achieve this without using a script like /.sh?
Things that i have attempted:
i have tried using the alias command in bashrc files
for example in bashrc file:
alias /usr/bin/a='java - jar'
but when i try to source the bashrc files, it gives me an invalid alias.
I know i can use a /.sh script to execute the command but that is not my intention to do it.

Have you tried to write a bash script with java -jar and execute it ?
You test.sh file will contain:
java -jar test.jar
And after that you can run
./test.sh
And offcourse you can put to bin directory or create an alias for that bash file

Writing a bash script to run a java program

I'm rank new to bash thus the question.
I've a java program that I've exported as a .jar.
This file when run as
java -jar somefile.jar
goes into an infinite loop and awaits a file name. Based on the correct file path it generates an output.
How do I write a bash script to do automated testing of this project.
I need the scrip to do the following -
Run the program, which is run the same command
provide an array of 5 files as an input to the program
For each file write the output to an log file.

This should do it.
#!/bin/bash
files="$#"
for i in $files;
do
echo "Doing $i"
java -jar somefile.jar <<< "$i"
done
Make sure you chmod u+x filename it first. Then call it like this:
./filename firstfile secondfile thirdfile etc.
Other:
As sjsam pointed out, the use of <<< is a strictly bash thing. You are apparently using bash ("I'm rank new to bash..."), but if you weren't, this would not work.

Suppose my java program is HelloWorld.java. We can run it in 2 ways:
1st using executable jar
2nd by running java class from terminal
create a new text file and name it hello.sh
In hello.sh
!/bin/bash
clear
java -jar HelloWorld.jar
Save it and open terminal:
1 navigate to directory where your HelloWorld.jar is present
2 give permission to terminal to run the bash script by using the following command
sudo chmod 754 hello.sh
3 run you script by running the following command
./hello.sh

How to run batch file with parameters in java?

I have created a jar file called test.jar under C:\jars. I have JAR file under the same location named run.bat and it contains the below code -
#echo off
set exec_path=C:\jars java -cp %exec_path%/test.jar; com.mycomp.myapp.MyProgram "%1"%*
#echo on
It is running successfully from command prompt with parameters.
Now I would like to run it from another JAVA program.
Please suggest.
Thanks!

I've encountered this issue before. The answer is that you have to run cmd.exe or bash or whatever shell you've got, then feed in the command to that process via the process input/output streams.
Process p = Runtime.getRuntime().exec("cmd");
p.getOutputStream().write("mybatch.bat\n");

Starting a blank console

IS there any way to start a blank console in Windows platform ?
I'm writing a CLI where i want to open a separate window where user can log in and write their own command. When executing with cmd /c start command, it starts windows standard console.
Is there any other command ???

Assuming you're trying to start a java jar file, use a command like this:
start /d "%~dp0" java -jar "%~dp0\fpa.jar"
%~dp0 expands to the drive letter and path in which the batch file is located. Use that if you want to want to make sure that the PWD when running is the same location as the batch file. Otherwise, juse use
start java -jar "%~dp0\fpa.jar"
This will make sure that the batch file works even if you run it when not in the same directory as the jar file, as long as the jar file is in the same directory as the batch file.
You may need to make sure that java is in your path by having a line like
set path=jre6\bin;%PATH%
Also, you can eliminate the command line windows that comes up (for a GUI program by example) by using javaw instead of java.

You can use batch file in windows which would in turn start application that would accept user input. Something similar to this :
start cmd /c myapp.bat

How do I run a java program from a different directory?

I have a java program that I would like to be able to run from anywhere on my machine. I would like to run it from my Cygwin command prompt. I've made scripts to call the java program. I added the location of the java program to the classpath, and the scripts work when I run them from the java program's directory. However, when I try to run from any other directory, I get:
java.lang.NoClassDefFoundError: commandprogram/CommandProgram
This is my script:
#!/bin/sh
CWD=`dirname "$0"`
java -cp "$CWD/classes;$CWD/lib/AJarFile.jar" commandprogram/CommandProgram
Changing the java line to the following:
java -cp "$CWD/classes;$CWD/classes/commandprogram;$CWD/lib/AJarFile.jar" CommandProgram
produces the same results.

add your directory to classpath example:
java -classpath commandprogram CommandProgram
or
java -classpath directory_to_program Program

After trying just about everything I could think of, I echoed out the command and saw that there was mixing of Cygwin paths and Windows paths. The solution was to change the script to:
#!/bin/sh
CWD=`dirname "$0"`
CWD=`cygpath -w "$CWD"`
java -cp "$CWD/classes;$CWD/lib/AJarFile.jar" commandprogram/CommandProgram
Then CWD changed to "C:\Program Files\..." instead of "/cygdrive/c/Program\ Files/..."
I had previously encountered this problem and solved it with the cygpath -w solution, but then changed my script slightly and didn't notice that the path problem came back.

you have to use a dot to separate packages, not a slash.
java -cp "$CWD/classes;$CWD/lib/AJarFile.jar" commandprogram.CommandProgram

The usual way of running a java file is to save it in the Java/Bin folder and Run cmd
C:\Program Files\Java\jdk1.7.0_05\bin> javac filename.java && java classname
If you save the file in different directory such as D:, you can use the following on the cmd prompt:
D:\Project java> set path=%path%;C:Program Files\Java\jdk1.7.0_05\bin