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Open another Java application from existing Java program

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.

the .jar file does not execute when I click on it

I know this question would sound very stupid, but this is my first java program after all.
K, the question is, when type this: java -jar JavaApplicationTest.jar the program executes without problems, but when I go to the folder where the JavaApplicationTest.jar file is, and click on it, it does not execute. I thought that .jar files were like .exe file, are they? I mean, in the way that we click on them and the program runs; 'cos the java virtual machine is running in the back ground.
Please, any help would be very much appreciated.

No, they aren't exactly like .exe. Only .exe is an .exe.
When you execute a JAR file, it's the Java JVM that's running, not your JAR file. The JVM opens the JAR, loads the .class byte code, and executes the main class that you specified in the META-INF.
I'm guessing that your Windows operating system is doing something besides running the JVM when you double click. Try right clicking and seeing what options your Windows operating system presents to you. If one of them is to unzip the file, you'll have to add running the JVM as another choice.

The jar-file runs. But there's a big difference between:
java -jar someJar and someJar.jar/respectively double-clicking on the jar.
The full command launches the jar in the same commandline, in which you have entered the command. Double-clicking on the jar creates a process aswell. But with a completely separate console-window that is hidden.

Java archive or jar is an archive of compiled java byte code and resources which can be run on a java virtual machine. ".exe" is a windows extension for directly executable code mostly used by installers or programs that do not need to be installed.

Running JARs without java -jar unix & windows?

I want to run a jar file in both unix and windows without have to call it directly with java like:
java -jar myjar.jar parameters
i want :
myjar.jar parameters
I've been reading allready -
Running a JAR file without directly calling `java`
Which seems like a very nice hack for unix .
Howerver , this wont work in windows.
I'm looking for a uniform solution that will work both on unix and windows , but I'm not sure there is such.
The solution has to be only once , and it has to include changes related to the jar only ,and not the operation systems - because this is a file to I'm suppling to a client.

What you are asking can't be done: Windows will load executable files only in the PE/COFF format used in .exe in .dll files.
What you can do instead is supply the users a "wrapper" program that starts the actual Java program. You could create the wrapper in C, which has several benefits: you can set an icon on the executable and associate the program with file types in the Windows Explorer. Batch files are a popular alternative; they are easier to create.

You can provide a script that starts your application for both Unix (.sh) and Windows (.bat). This seems to be the preferred approach for many companies. An example would be JBoss Server where a run.bat is provided for Windows and a run.sh is for Unix. These scripts set the appropriate environment variables, classpath, etc and then call java.

You can write your own bash and batch/powershell scripts. As for windows, you can try Launch4J. It should be easier than writing elaborate scripts from scratch.
Be aware that you can only provide wrappers to make the execution simpler (one click). Java has to be run anyway. Either explicitly, by the user, or as part of a script. You can't do without it.

C++ Prevent the opening of an output window

I have created a java program which has been compiled into a jar file.
Now to make it exe, I have a C++ script that launches the jar file.
It launches fine, but the black cmd screen (or C++'s default console window) stays open until the java program is closed.
Is there anyway for me to make it so the black output window doesn't open at all?
(I am using Code::Blocks IDE)

I ran into this problem once... if you are using Swing, try to run with "javaw", not "java", that worked for me.

Can my Java software be transformed to .exe software?

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