I have created program that takes input from System.in and output to System.out. I create the executable jar and I want to run it without entering java -jar in windows. Is there any way to do this?
There are a number of ways to do this. The simplest way is to create a batch (.bat file) file that invokes it for you. There are also a number of solutions out there that will create a Windows executable from a jar file. Note: these programs don't compile the byte code, they just create an executable wrapper around the jar. One option is Jar2Exe but there are quite a few. JSmooth is another option I have used before that works quite well. Another advantage to a program like this is you can bundle all dependent jars into the same executable file as well. Some google searching for "jar to exe" should find you one that works for your solution.
You could write a .bat script that will start your jar.
On windows a simple double-click on the jar file should open it if the environment is well set.
You use the "start" command like "C:\> start myJarFile.jar".
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I've written a few java applications (desktop, no browser involved) for friends, some of whom are less technical than I am. They use Windows, Linux and Macs. Originally I just used javac to generate bunches of .class files, zipped it all up and had them unpack it all. It works, but they had to install the JRE (terrifying for some), write a script to run java or javaw followed by command line args, app name, more arguments (incomprehensible for some), mark the script executable... I got mocked, somewhat rightfully, for a geek solution. They wanted to download from a website, doubleclick and be up and running.
I thought creating a .jar file would be the solution. It didn't help. In Eclipse, the options seem to be "create a jar file", which lets me include the handful of resources (.png files mostly) the apps needs, but the result isn't runnable from a command line. Or, create an executable .jar file, which doesn't seem (at least from Eclipse) to have a way to include resources - and the resulting .jar file doesn't start when double-clicked, even when I set the execute bit, even though the default run environment points to the Java suit. Even with a .jar file, I'm stuck with having them script "java -jar App...", and that's pretty much a dealbreaker.
I'm missing something. The point of Java is platform independence. Is there a platform independent way to have them download a single file, double click it and have it off and running?
If you are trying to create a runnable jar file from your project in Eclipse, you have to select that option when exporting. You can do this by Export > Java > Runnable Jar File. If you only select the Jar File option, you won't be able to run it.
If you want to wrap your application as a .exe, you can use launch4j. Here's a thread that explains it a little more and has some other options.
Hello all :) I love stackoverflow where I always find answers but this time I could not so personally asking... Its bit lengthy please go through it.
I am creating a java application where one of my resource is an exe file which I need to call in the java code. But later I would convert the whole java code to a JAR file... and I would add the JAR file and the exe file for the Setup file for installation process. So when I extract the files I want my JAR file to call the exe file while running... I am doing this all in Eclipse :)
So my doubt comes here which path I should put up in the java code... ? So that it will always call the file the exe file from the same directory where the JAR file is also present.. :)
Any help would be great :) Thank you in advance :)
Assuming that you control the whole installation process; and that you also control the script that later starts a JRE to run your JAR within; my suggestion would be: simply use a property here.
In other words; your installer knows that it copied JAR and EXE to D:\example\ for example. Then just make sure that your JAR is started like:
java -jar D:\example\your.jar -D your_path=D:\example
(this is just meant as example, you would have to work that out, probably the \ in there need some special treatment for example)
Then your application can simply query for that system property "your_path" and take the value from there.
Alternatively, you could try this solution that works "pure java".
I think I have seen this done, but am not sure where. What I want to do is to create a bat file I can package with my class files when sending to a friend to show them progress/ask advice on non programming matters. My friend is not very handy when it comes to code and doesn't like changing computer settings. Just using java myClass as a command line won't work here because although my friend does have java installed, he has not set his windows environment variables so his command prompt knows where to find java.
What kind of line would I need to add to my batch file to make it so it can compensate for problems like this?
Create a manifest file (manifest.txt):
Main-Class: com.mycompany.myapp.MyMainClass
Package your app as a jar:
jar cfm myjarfile.jar manifest.txt *.class
Create a batch file:
start myjarfile.jar
If it is about sharing and running a single java file without jar dependencies. And you are only worried about the java runtime environment setup, then you can use online java code compilers and executors. Here is one:
http://javalaunch.com/JavaLaunch.jsp
You can google for more!
Use an IDE, NetBeans or eclipse and package your files as a Jar file.. that can be executed directly and you do not need to worry about dependencies, other classes or libraries.
so, I've been doing some searching, and i can find somethings on how to run an external application, but i cant get them to work! I've been working on this for a while, and its really annoying.
what i want to do is run a .jar file in the directory
C:\Program Files\AVTECH\NPS\Files\bin\NPS.jar
and I've tried a bunch of different things with the code
Process p = Runtime.getRuntime().exec("dir goes here");.
also
Process p = Runtime.getRuntime().exec("C:\\Program Files\\AVTECH\NPS\\Files\\bin\\NPS.jar");.
if i'm correct, it uses command prompt to do this? or at least the MS-DOS language. i did some of that kind of thing a few years ago, but i don't remember how one would do this... I've never worked with this kind of thing in java before...
could someone help please? thanks in advance.
Runtime.exec() is working just like if you were typing a command.
Launching a jar file is not working : you have to invoke
java -jar /path/to/my/jar
Check Oracle's documentation on how to execute a jar file.
The actual command should be java -jar C:\\Program Files\\AVTECH\NPS\\Files\\bin\\NPS.jar. I mean -- if the jar file is indeed executable, this doesn't mean it will run, by just trying to invoke it. You need to tell Java to run it as shown above.
In addition, MS-DOS is not a language -- it stands for Microsoft Disk Operating System. Nowadays, you have this as a Command-line Prompt (Shell) built into Windows.
You need to run the command as a call to the executable and a set of arguments. Check this version of Runtime.exec(String[] cmdarray). If need be, there's also a version of Runtime.exec() that takes a base directory in which to start the executable.
Without learning new programing languages, can we using Java get .exe (executable windows file) software directly? And is there away to make .jar (Java ARchive) software transform to.exe (executable windows file)?
Would this conversion effect the performance of the software?
One of the important points of Java is that it'll run on any platform (e.g. Windows, Linux, etc) that has a suitable Java Virtual Machine (JVM) installed. A .exe file is compiled to work on only one platform.
What you think you want is to turn a .jar into an .exe so you can launch it easily. What I expect you really want is just an easy way of launching a Java app that anybody can understand, including your parents.
The easiest way of doing this is to create a Windows batch file that launches your Java app. One of line of script, one new file, one new instruction to your users - "Double click on runme.bat"
There are ways of turning a .jar into an .exe, but you should think about whether that's really what you want, and if so, why.
Note: you can launch a .jar in Windows by just double clicking on it, as long as the main class is specified in the manifest. You might want to look into tools like Apache Ant to simplify building .jars and their manifests. Just a thought.
EDIT:
A batch file in Windows is a simple text file that contains commands. You can test the commands by running them in the command prompt (Start -> Run -> cmd). When you run a batch file the commands in it are just fed to the command prompt one at a time.
How to run a Jar from the command prompt: "java -jar myfile.jar"
If you create a batch file (.bat - use Notepad or your favourite text editor) containing "java -jar myfile.jar" (without the quotes!) then double-clicking it will launch the main class specified in the manifest of myfile.jar. myfile.jar has to be in the same folder as the batch file, though.
If you use the command "java -jar lib\myfile.jar" (again, without the quotes) then your batch file will run myfile.jar, which needs to be in a folder called lib that's in the same folder as the batch file. Use this approach when you have a whole load of Jars with your application and you don't want to shove them in the user's face :)
Note that moving the batch file will break it, unless it uses absolute paths to the jar file - e.g. "java -jar C:\dev\myfile.jar". Of course, if you use absolute paths then moving the Jar will break the batch file anyway :)
Also, note that you should be able to run a Jar file just by doubling clicking on it in Windows, as long as the main class is specified in the manifest. Give it a try. Of course, convincing your users that they can double click on it is another matter entirely...
As a final note, if you use a batch file, your users will get a nice command prompt window sitting in the background until your Java app closes. That is, unless you start your batch file command with "start". E.g. "start java -jar myfile.jar". If you have your app configured to log to System.out or System.err, you will still get a command prompt when your app writes to either of those streams, though.
Final final note, in the Linux world the equivalent of batch files are shell scripts.
You can launch a .exe from java with Runtime.exec() or ProcessBuilder.
You can make a .exe launcher with http://launch4j.sourceforge.net/
Yes, it is possible: http://www.excelsior-usa.com/articles/java-to-exe.html
I'm not sure if this is an appropriate answer because I don't work with Java but could you not using a shortcut file pointing to the java runtime and pass the jar as an argument, this
I realise this is not the only way, nor probably the best way but to me it seams a little better than creating a batch or converting to an exe file if all you're looking for is a convienient way to launch a java app
The very simplest way is to write a windows batch (.bat) file which will start the application.
I was using a wrapper for java to make exe files for a pretty long time:
JStart32
It is just a wrapper for *.jar files.
But ask yourself:
Wouldn't an exe kill the purpose of javas platform independency?
Check out jsmooth (free) and exe4j and you might want to read make your swing app go native