I am attempting to port an application that was written with a combination of c++ for the back end, and java for the front end. This application relies on the library opencv 2.4.13, which is outdated, as well as multiple other libraries. The concern i have is that i do not want the end user to need to install these dependant programs, as they have been proving challenging to install on any but a select few linux distributions. I believe the term i am looking for is statically linking, but i'm a bit unfamiliar with c++ compilation at the moment, so i am unsure the steps i need to take to make these files portable. The java application requires these files to be libraries, and while i have managed to get them to compile on one machine, the problem seems to be getting them to run on a different one after compilation.
Don't bother - this might also give you licensing problems, depending on what libraries you need.
Instead, just figure out what platforms your application is supposed to run on and package the libraries for each platform with your jar - or download them at startup, or provide them as a separate package. The exact mechanics you choose depend on your use case, the point is you don't need to rely on system wide installs.
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I found some reference that says I can add #!/usr/bin/java --source 12 at the beginning of the file and run the file directly from the terminal.
I am able to run using this on my local machine, however, when I tried the same on Github action I'm getting the error error: invalid value for --source option: 12
I'm not really an expert in shell scripting or java, can someone help me understand what this --source means is it the java version, I tried setting up the same version (jdk18) on Github action but still did not work.
java (the runtime executable) can only run class files. Until, that is, java12, where a normal JDK distribution (and not the bizarro JREs that some packagers like Azul publish ^1) has a java.exe that can run java files straight up. It's simple sugar - the compiler is still involved, of course. It's just that java will execute it for you.
You don't need --source 12; just java MySourceFile.java is fine. Edit that comment at the top of your source file, it should just be #!/usr/bin/java. The thing you do need is that java on your command line PATH is a java v12 or higher, and it is not. There isn't anything your java source file can do about this, you're going to have to impose on your users to have at least java12 installed or this simply does not and can not be made to work. It looks like you're on some linux distro or other; apt or yum or snap or whatever package manager you have will tell you how to fix this: Install java17, and uninstall the rest or use java-alternatives or whatever mechanism your package manager has to set the default executable (the one /usr/bin/java links to). Read the documentation of the package supplying java17, possibly following some links to the generalized java infrastructure package, it should tell you.
Mostly this is a red herring, this just isn't how java files are distributed. It's virtually pointless because:
Java is not a language that tends to be used for quick shell script-esque things. Such things tend to be self-fulfilling prophecies: Because nobody does this, library authors aren't thinking about it when they develop their APIs and the users of their libraries won't file enhancement requests for this either. Because common libraries aren't convenient when used for quick off-the-cuff shell scripts, java isn't used for it, thus perpetuating the cycle.
Any serious java app would definitely involve packages, dependencies, and more - and such apps cannot be run like this.
Class files are as platform agnostic as source files are. There is no sane reason to distribute java-written shell-script-esque tooling as a source file instead of a jar, except for off-the-cuff editing off them, which gets you right back to point #1 and #4.
The java core APIs work on a model of lowest common denominator: If there is a major OS that cannot or doesn't work in a certain way, then java simply does not expose this at all. For example, on all posix systems (i.e. pretty much every major OS except windows), you have your usual TERM, KILL, HUP, etc signals. Java core libs don't let you interact with them (unless you dip into hidden sun.misc.* API which doesn't reliably work in the first place). This makes java extra unsuitable for quick command line scripting where you want a different model: If at least one OS can do it, the language should have a library for it, and that library should simply fast-crash if you attempt to use it on an OS that doesn't support it. One easy way around this is a third party library that adds support for OS-specific stuff, but your model of distribution (stick #!/usr/bin/java at the top and distribute a source file) cannot include dependencies.
Java as a runtime model is mostly focused on running things eventually very quickly, at the cost of starting off slowly. This is fantastic for web servers which need to run efficiently but will be running for quite some time. It's utterly unsuitable for shell scripting, though.
CONCLUSION: You don't want to stick #!/usr/bin/java at the top even if you could make it work.
[1] A JRE is a java distribution without compilers and other development tools like jstack. These cannot run java SomeSourceFile.java, obviously; they do not have a compiler. However, JREs died - there are no JREs anymore; JDK8 is the last one that shipped with an official JRE. The JRE serves as a distribution model: The end user installs a JRE, and you ship your jars to them. This model is obsolete (you are now responsible to get something that can run your class files on the deployment machine), and therefore JREs died. However, some packagers of OpenJDK builds, such as Azul, still publish them, confusing matters. Hence, 'bizarro'. Azul and co have relatively good reasons for doing it, but, you shouldn't be using these unless you really know what you are doing.
Now, don't get me wrong, I am a very competent programmer, but when I program, I typically develop things for the web using scripting languages like JavaScript, PHP, Python, SQL, etc. If I want to develop Java software (I am relatively experienced in Java), how do I distribute it?
Is there any good way to package up Java software in a nice little executable, send it out, and have it run? Alternatively, is there any good way to package up Java in some sort of installer, and send it out to be installed and run?
I'm using Launch4J http://launch4j.sourceforge.net/ it will generate an .exe executable for Windows, if the targeted system don't have JVM, it will tell user to download and get JVM.
You can package Java applications in so called jar-files using the jar tool or any competent Java IDE. These jar-files are self-contained and seldom need any installer.
These .jar files can easily be distributed and executed.
If you're used to web-development, you may also be interested in the Java Webstart technology.
Some links to get you started.
Export to a .jar-file in Eclipse
Lesson: Java Webstart
I have found two approaches to work well, depending on the needs of the end user.
1) Java WebStart - allows for central distribution and easy maintenance, but works best for online users. Require you to have a web site to locate the files - these days this is easy to do on the Google Application Engine.
2) Wrapping up the Java program in a single jar using one-jar, and then using jsmooth to generate an .EXE file which ensures Java is available, extracts the jar-file and invokes Java on it. This works well for users not always on the net, where you want the launch process to be transparent, but is less easy to upgrade than the webstart approach.
I use Maven to handle all the dependencies of my projects and that way when you utilise Maven to build your projects they will compile into one nice executable jar that contains everything so you dont need to worry about getting all your third-party jars in the right place etc.
There are a couple of ways: one is to create an installer that allows your user to install and run it. For this you can take a look at NSIS.... or you can just use Java Web Start where your user can just click the link and launch your application.
Here you will find a large set of options: Open Source Installers Generators in JavaIt is very useful for the "naive" customer or user of your application, to make the installation process as painless as possible. Let them install whatever is needed, DBMS, JVM, JMF and additional options via one installer.
You can also consider use one of the rich client platforms available for Java. The learning curve is probably a lot higher than just creating a jar file and ship it, but you will get a lot for free when it comes to distribution. (Think Eclipse with auto update through an update site).
Do a search for "Eclipse RCP" and "Netbeans RCP" and you'll find the two biggest contenders here. I also performed a serach for "eclipse RCP installer" and one of the hits seems interesting:
http://download.instantiations.com/RCPPackagerDoc/integration/latest/docs/html/gettingstarted/GenInstaller.html
I personally like izpack. It generates a jar file installer that you could wrap up in launch4j, supports things like windows specific shortcuts, is highly customisable through XML and hooks directly into ant.
OneJar is great for smaller stuff, but for larger programs or applications it's nowhere near as flexible and in my experience is rather slow.
Hello you can make an installer for your application.
In the link below you will find a nice help about izpack installer.
http://www.imrantariq.com/blog/?p=89
Link below contains a detailed pdf to make installer with izpack.
http://www.imrantariq.com/blog/?attachment_id=112
cheers
I would like to know if there is any way that I could build a very simple GUI app (it doesn't even have to look good) that will run on a fresh install of Windows Vista and OS X with no other installations needed by the user. I would perfer not to use Java (just out of personal programming preference). I will use it though, if it is the only way. Specically, I am wondering if I can write a swing app with Scala or Groovy and run in on windows without them having to install anything. Sorry if this is a silly question, I am a Obj-C developer by trade.
You can pack the Scala jars into your own, which should work as long as Java is installed (which it usually is on a 3rd party vendor install of Vista or OS X). If you use Java web start, no installations are needed beyond Java itself. Plus, if you're going to install your own code, why not just copy along the Scala jars also?
If you really mean a fresh install--nothing but what the OS provides--then no, I don't think so.
Edit: You do always have javascript on the browser(s). I assume this won't cut it for what you want?
If you really, really don't want to install anything (or carry anything in your app), then write the application as a web app (possibly a javascript app). Then any user can run that UI from any machine with a decent browser. But then, this will require that you host the app somewhere.
If that is not an option, you can develop your app to as a single html/xhtml file containing a self-contained, self-modifiable javascript application (like TiddlyWiki which I use a lot). Then the user user can download on it on his machine, point his browser to it and voila.
If you combine javascript with HTML5 (and assuming the user has a HTML5 compliant browser like safari), your application can use localStorage to keep its state in the user's machine (thus no longer needing to be self-modifiable to save state as TiddlyWiki does.)
But this would break your rule of not downloading anything on the user's host machine. It is a chicken-and-egg problem that has no solution since each OS implements its own set of application libraries. For multi-platform support, you must use a layer that abstracts out differences between operating systems, be it a vm (like JVM, Ruby or Mono) or a set of libraries (Qt, Gnome).
As far as i know you won't be able to accomplish that with no other installations needed by the user. If you violate this restriction, mono (with gtk#) is a good choice.
Scala and Groovy will have the same deployment issues as Java; all of these require a JVM to be installed. You generally have to first install the JVM (which is not included with Windows) and then install your program. Java is included in OS X, however.
It is possible to use Ruby or Python and one of the cross platform libraries (like wxWidgets) and compile these to an executable file that includes the entire set of runtime libraries (e.g. all of ruby and python).
REAL Studio (formally REALbasic) certainly meets this requirement. It creates native applications that have no external dependencies for OS X and Windows (plus Linux).
In theory you could write a .net application using Mono that it should run without issues on any other one with the .net runtime environment installed.
But I'm not sure if it will work on practice.
I've had some success with XulRunner
There's also a couple of recommendations from these questions I asked
Building Cross Platform app - recommendation
Building XUL app a-la SongBird
XULRunner is pretty cool once you get into it, but it's a tad confusing at first (I thought).. the folks on the mozilla google groups are really nice and helpful though!
I am working on a java based application and we are looking to ease our deployment of updates. Up until now, we've always simply sent out new install packs & had the sysadmin's on our customer sites roll out the upgrades - painful for a large number of users.
what I'd like to do is something similar to java webstart (or eclipse p2) - when the application starts, it checks for updates in a specified location and then downloads the updates prior to starting.
But here's my problem - I want more control over what's done outside of the scope of plugins & jar files. For example:
I'd like to be able to upate my JVM (we ship a modified version with additional security features).
I need to install DLL's - possibly local to the jar files, sometimes to windows
Occasiontally run MSI's to install windows components (e.g. printer drivers).
I need to modify config files & the registry.
I have found a few applications that support this (such as AppLifeUpdate at http://www.kineticjump.com/) but they tend to be .NET focused and it seems a bit perverse to introduce a .NET dependancy on a java application ;)
I know I could write my own here, but if there is already a 3rd party library out there that supports this kind of facility, then it would make my life a lot easier.
So, has anyone else had a similar problem & knows of some products I could look at?
Thanks, Brian.
I have done similar things but on Linux/Unix, so can't suggest any specific products for Windows. But I always found helpful to either package everything in OS format and distribute everything that way (rpms, debian pkg, Solaris pkg, ...) or have the platform deployed through OS mechanisms and have the application deployed through Java mechanism (Web start).
The reason is that sysadmins typically don't like things that magically update themselves without them knowing or in a way that does not follow standard practices. That is: you can't expect to make your life easier if you are not sure that you are not making their life more difficult...
Also: whatever work I do at the OS level, I do it with OS tools. If on Windows it means using .NET, I would very much consider using that...
Hope this helps!
While i'm developing in C/C++ and Java, i simply make a compile.bat script that does everything, that's fine for me. Why should i use make and why should i use ant?
Suppose you have 1000 source files and change just one of them. With your .bat script you will have to recompile the lot, with make you recompile just the one that changed. This can save quite a bit (read hours on a big project) of time.
Even better, if you change one of your header files, make will re-compile only the source files that use that header.
These are the two main features that have meant make and its offspring are used for all serious software development with compiled languages.
With a build file, you can automate more than just compiling your code; you can run unit tests, gather metrics, package build artifacts for deployment, and more.
An advantage, of sorts, of Ant is that it inspired tools for other platforms - NAnt for .NET, Phing for PHP. They do the same things, and work in the same way.
As long as you develop for yourself under Windows: suit yourself.
But if you start to develop with others Ant and Make are a standard to describe how your App is built.
There may be several reasons:
- because you are not the only one in the project
- because somebody will have to care about the build script when you left
- because a compile.bat script is not platform independent
- because the policy of the project defines the build technology, e.g. for the entire enterprise
I recently read a funny article about build tools. For you only the first part may be of any interest (before the maven bashing starts)
For one thing, make and ant both keep track of which files have already been compiled, so it does not redo work if it isn't needed.
You gain some platform-neutrality (how can I run your batch-script on my linux-box). But more important: build-tools have support for dependency-resolution. Scripts lack this and have to build it on their own.
Say you have targets A, B and C. B and C both depend on A. In an script they call the subroutine A. If you now create a new target D, that depends on B and C, than you will execute A twice. Build-tools recognize this and execute A only once.
Because this situation is typical for task involving compiling, building a distribution, testing, building documentation etc. build-tools are useful for software-development.
It would be possible to use a .bat file -- or bash or another flavor of shell script -- to do everything Ant can do, I believe. But it's far easier to do many things in Ant...
create/move/delete files and directories
apply filter tokens
run unit tests
package a jar, zip, or war properly
Many projects need to do these things, in addition to compiling, when they build.
Also Ant is platform-independent, so you can collaborate with those who use other operating systems.
But why stop at Ant? Apache Maven offers even more compelling features.
Make and Ant really come into their own when used with automated build systems or continuous integration.
The requirements for production builds, test builds and development builds are often different, and on a multi-person team, different developers set up their development environments in different ways.
Having a definitive build process solves the "Works on My Machine" (WOMM) problems that arise whenever the application needs to be built on a different machine from the one that it was developed on. It is the ultimate arbiter when one developer checks in code that doesn't work on another developer's machine. If the build process doesn't produce working software, then the first developer's check-in was broken. If it does produce working software then the second developer's development environment is broken - unless proven otherwise.