I am looking for something similar to GraphViz, but that would allow me to generate the graphs without having to install the program on the computer. As I understand, I would have to make external calls to the program after generating a DOT file in order to make this work, but I would like to package my program into an executable jar file that runs as a Stand alone app. Is there something that would allow me to do this with JAVA?
If there are any good tutorials out there please link them here.
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I would like to get the path to the working directory of a specific process (for example for the PID of the process). I am Not Talking about the working or current Directory of the process where my Java Code is running. Its a simple task with Linux, but for Windows i cant find a proper solution. Furthermore, it would be nice, if its a Command or a Framework for Java, because i will need the path in my Code. I am not looking for the path to the executable, also Not for a solution with wmic or process explorer.
Already thanks for the help.
I already tried commands like tlist and wmic, but those solutions cant be utilize in my code. I am looking for a solution that i can use without special installations on Windows.
JNI and JNA provide means to call directly into native libraries from Java code, and it is feasible to use these to call out to Windows libraries.
There is a github project that appears to be close to the need: https://github.com/kohsuke/winp. Perhaps you can add the needed code and send up a pull request, or fork the project.
Note that any solution here is going to be windows-specific, meaning the application using it will not run on another platform. Given the nature of the question, that doesn't sound like it would ever be a concern.
I wrote a simple java code that would take simple inputs from the user in the command window (of eclipse for me) using nextInt() and nextLine(). However, I realized that others need JRE (I believe?) on their computer to run the executable jar file made. So I was wondering if there is a way to get around that by making the app produce a window that is like the command window to have the same interaction as the command window in eclipse.
So, if I were to run the .jar or .exe then a simple window would pop up that acts like the console of eclipse displaying lines from System.out.println() and etc.
To run a java program you need the jre. There is no way around that.
If you need the console, nothing is stopping you from running the java program from the windows command line, which will do exactly what you ask for.
You still need the JRE.
Unfortunately, when starting to learn Java with Eclipse, many people miss the opportunity to at least start to understand how to do the same from the command line, which is, if you ask me, good to know.
For programs written in Java, they are compiled as a jar file, like you mentioned, and how these compiled versions of your source code differs from many other programming languages is that they do not contain the assembly/machine code like for example a compiled C program would have. They are instead compiled as bytecode. Which is special code for execution by a Java Virtual Machine. Here is a good Wikipedia reference: link
To answer your question, yes, others need a JRE (Java Runtime Environment) and this can be either:
Installed by themselves (this is what you mentioned)
Packaged together with your java app, to provide a download-and-click experience.
For option 1, assuming they already have it installed, they can simply run it by executing the jar file with javaw, more information on that is in this previously answered SO question
For option 2, the process is fairly lengthy and I'll point you to the official docs to refer to: self contained executables and Deploying java apps
If you have a more complex project with third party libraries and what not, look at this SO question
In the past, I've also found launch4j, a cross-platform wrapper to be very useful, it automates the process of going from jar to an executable (made a simple game that using Swing, simple and ugly thing it was), but the user still needs a JRE, nonetheless. :)
Hope this helps!
I am writing a minesweeper program in Netbeans, with java. I would like my friends to be able to try it, preferably on from there own computer, over the web. I have already made a .jar file, but do not know if how to proceed, or even if this is possible. How would I put it on the web so they can try it out?
Why not just send them the jar file? Then, they can just run it on their computer.
To put the program in a webpage, you need to put it in an applet, which will require some extra work (and maybe some changes to your code).
http://java.sun.com/applets/
You need JavaWS (Java Web start )
Check this link
http://docs.oracle.com/javase/1.5.0/docs/guide/javaws/developersguide/syntax.html
One option is to write your game as an Applet.
See the standard tutorial or you can google for many others.
I made a simple command-line based game in java, only two classes (using Eclipse). But I was wondering how I can make this into a usable application for anyone, without running it through eclipse (ie send it to someone who knows nothing about java but would still be able to play the game)? Thanks!
You want to create a runnable jar file.
Eclipse has an option for this in the "Export" menu. For more options, search for "executable jar file" here or on Google.
You want to make sure that you also include any jar files your code depends on as well (Eclipse can also do that for you).
Users will be able to start this by double-clicking on the file on most platforms. If you need better integration (such as a custom icon), you will need to bundle it up further into an OS-specific executable. But for starters, a simple runnable jar works fine.
send it to someone who knows nothing about java
You need to get them to at least install the Java runtime on their machine (if it is not already there).
Just to be clear, "command-line" and "knows nothing about java" are probably not going to work very well for you given that:
java is OS agnostic, therefore, if you send (presumably) a jar file to say...your grandma and she has a mac and you have a PC chances are her getting it to work is not going to be "out of the box easy" so to speak.
Left with this, I think you have a couple choices...first off, you do need to package your classes - a runnable jar will work fine. Aside from that, you will most likely have to build OS specific scripts (batch scripts for Windows, shell scripts for unix, etc.) and you will have to hand these out with your jar file. That being said, the intended user will still need to have java installed, and the batch scripts themselves are not likely to be trivial endeavors.
Your next option would be to use JNLP. However, I don't think JNLP has a command line mode, so you will likely have to simulate a console with something like a JTextArea.
As far as I see it, your last option it to use one of the many products (not sure if there are any free ones) that package java into native code. I think Exe4j is one such example - but, like I said, I am not sure if there are any free ones and I am not sure how hard they are to use.
Best of luck, and if you can't get your jar to work you should probably move that to its own question.
I created a small application that, when run, creates or updates some tables in a database by extracting data from some PDF files. Everything works fine in this desktop application, but the next step for me would be to make it possible for an administrator on a website to upload a PDF file and my Java program would then run and update the tables accordingly.
The problem is I have no idea where to start with this (the site isn't done yet, but I'm running some tests and it is going to be coded in PHP). I'd like to know what kind of technologies I need to let the server run the program and update everything as it would in the offline version. Sometimes it takes a while to update everything, so ideally, the user uploading the PDF could continue browsing other pages while the server does its job. (I'll probably implement something that when the server is done processing the file, it says if the program ended successfully or not in a log file)
Can someone tell me what terms to search for on Google or give me some pointers? I haven't chosen where my website is going to be hosted either, so if someone could tell me what to look for to know if they support running applications like this, I'd really appreciate it as well!
This could also apply to other programming languages as I know a bit of Python and C++ as well, so in the future I might have some applications in those languages I'll want to use on the web.
If I'm not approaching this the right way, I'm open to other suggestions, but the best solution would be to keep my Java program intact as I know it works exactly like I want it to and I'd rather not have to start it all over again.
If your host is *NIX based you can use crontab (Automatic Task Scheduler) to run your program at set intervals. Make it check if a "new" PDF exists, and run the program if there is. There may be a way to use Windows Task Scheduler type programs to do it on Windows. This is probably the easiest way.
Alternately you can use You can use shell_exec() in your php to execute a command on your *NIX system directly to run your java program.