I'm building a Java tutorial where there is a button when clicked, opens a notepad application which I built. However how do I go about opening the notepad application in the ActionListener? Should I use ProcessBuilder?
If your separate program is a compiled .jar file, use the following code to launch it, but note you will not have any control over it.
Runtime.getRuntime().exec("java -jar 'path/to/file.jar'");
Note this method returns a Process object, which you can then modify to your individual needs.
Related
Tools: Win 7, Launch4J 3.5, Simple Hello world Java console app (bundled in a JAR file)
Hello all,
I have a basic JAVA console application that doesn't request any inputs, just a simple application that opens a console window and displays Hello World text.
I built it so simple so I can experiment with Launch4J 3.5 and build an executable file from the jar file.
Everything looks fine, the exe builds successfully but when I launch it nothing happens, I get the hour glass for a few seconds then nothing. I check the Task Manager and there's no process stuck in there.
See my settings in Launch4J, I only filled in the basics, I tried with and without an entry in the Wrapper manifest field:
Output file: C:\Development\SFDC\ProjectX\out\exe\ProjectX.exe
Jar: C:\Development\SFDC\ProjectX\out\artifacts\ProjectX_jar\ProjectX.jar
Wrapper manifest: C:\Launch4j\manifest\uac.exe.manifest (also tried with leaving this blank)
The rest is all left as default.
If by launching you mean double clicking it, no - nothing you can see will happen; you have to 'tell' Java to run your application with an associated console. To do this, you may create a new .bat file: Simply open a text editor and insert the following line:
java -jar NAME.jar
where "NAME" is the name of your application. Save the text file in .bat format, not in .txt, and place it in the same directory as your application. You can launch your application by double-clicking that file.
The reason it does not pop up in your task manager is because probably (I cannot know) your application only prints out a simple message and does nothing more. In non-console mode, it will just call your print (println or any other console) method without having any visual effect as there is no console to print the message to. In both cases however, if you only print something and do not perform other operations that 'last', such as listening for input, your programm will terminate as it has reached the end of the main method.
Yes. You do need to use the console mode.
You also do need to have some method of keeping the console window open, because it closes the console the moment the program terminates. Use scan.nextLine(); or Thread.sleep(i) if you really need to.
Possibly you need to use launch4j in console mode, see this answer: lauch4j hello world program
I need to run an external JAR file (which is minecraft) within the window (form) of a VB.NET application, so like having the program in the center and additional text I like around it.
Is this possible, and if so, how?
With shell() command and java.exe -jar yourJarPath/file.jar It should works, if my memory of VB is good.
First i want to convey is, my Question is Not duplicate to this Question, How can I convert my Java program to an .exe file?.
Since My question, I had wrote a Swing program, in that program, there is a Button called "Generate EXE" , when the Button is clicked i have to generate the EXE of that program, so i need to create EXE via Java Code, i had created EXE using Advance Installer IDE http://www.advancedinstaller.com/user-guide/tutorial-java.html, But now my requirement is i have to generate EXE via Java code not using IDE by manually, my java code has create the EXE.
Thanks
This is not how to make an exe but since I think these solutions do the same job and I would personally prefer them, will post it anyway:
Create executable jar instead of exe
generate a script (in your case probably .bat file) which will run the java with appropriate parameters for you
If the exe is absolute requirement, convert the .bat file to exe (google for bat to exe)
I encountered this problem several times. If I pack a Java application in an executable jar file that takes arguments from a user, then the user have to invoke the program (jar file) from the command prompt by the following command:
java -jar "jar-file-name.jar"
But I want that whenever a user double clicks on the executable jar file (that needs arguments from the user), a window (command-prompt window) appears that would appear if we had invoked the jar file from the command-prompt.
I know one solution to this is using batch file .bat to run the jar file. Is there any other solution?
To explain why:
There are 2 java JVM exe launchers:
java.exe: console based - provides console input/output.
javaw.exe: for GUI apps - hides the console.
JAR file extensions are associated with javaw.exe by default, which is why you don't get a console when you double-click them.
The answers others have given, and adding my own:
rewrite your app so that it uses Java GUI items for input and output instead of System.in/System.out. This may be over-complex for what you require.
You mentioned creating a batch file so that the console-based Java JVM (java.exe) is run, You could also create a windows shortcut specifying the command line: java -jar jar-file-name.jar
You could change the windows file associations for .jar (but generally this is a bad idea -- new Java installs may reset this, and it will mean all java apps run from jars will have a console)
You could use a Java launcher like WinRun4J which allows you to simply drop a double-clickable EXE with an icon and a config file that specifies how your app should be run (with/without console, and with any other JVM and command line parameters )
Personally I went for the last option in my project - I made my jar file non-executable, and the user has to double-click the EXE. It also allowed me to specify a nice icon for my project, and provide multiple options on launch (debug/non-debug mode) simply by having a different exe/config file.
You would need to reassign the explorer association for ".jar" to java.exe instead of javaw.exe. This is somewhat of a questionable thing to do - it might make more sense to create your console output window. You can, of course, trivially pop up a dialog for user input of required execution parameters if they are not supplied on the command line.
There is working code for a console output JTextArea here.
This is an operating system feature.
If you want full control, then you must provide this functionality inside your program (or with a wrapper class.
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