General JAR Questions 101

Question

I just completed my first ever app using the Netbeans IDE 3.6 w / sdk 1.4.2_04
My GUI app has a main class name of : "AddRFSwitchMain" residing in a package named "AddRFSwitchPac" all in a project folder named "OW_A"
My app requires the resources of an external multi -container "OneWireAPI" jar file.
My app also makes use of the timer bean that came already residing in the netbeans IDE bean palette.
All of the GUI code was constructed by using the GUI form builder tool including the timer bean56.
Question:
(1) To run my app outside of the IDE, I created a "jar file recipe" named "OWProject" This OWProject recipe then becomes my "compiled jar" named "ProjectOW" and runs fine when mounted "inside" the IDE . It looks to me like my "ProjectOW.jar" only makes "file location references" to the needed external "OneWireAPI.jar" I thought that my jar file would contain the "actual files" of the needed "external files" inside my jar .... is this not true? ..... as it stands, to run my app as a stand alone on another computer , with an installed "jre" , I would need to also include the "OneWireAPI".jar also to be installed on a computer running my app.
(other questions to follow this one)

Answer 1

>
OK ... so ... "third party software" is only made
reference to its "location" as spec'd in my app's
manifest.
.... and I do this in the " Class-Path: " of my app's
manifest.Yes. (see below)
>
.... and I can include the "external jar" in my app's
package for transport to other computers as one Jar.I'm not sure if that would work. (a jar within a jar). ??
How about something like this:
\Package Folder\
     - MyApp.jar (the main jar)
     \bin\    (folder)
          - Other Jar needed for execution of the programThen in your main jar's manifest, include "bin/OtherJar.jar".
So the second jar will be packaged separately, away in a folder that clearly states what it contains.
All the user would have to do is to execute the main jar. this is the only file they would have to see, from an
execution perspective.
Question:
(2) As my app now stands in the netbeans IDE , my app
"imports" these required external files from thier
respective locations "mounted" in my IDE. ... When I
move these external files to my "Package folder" ..I
must now go back into my app and change any location
reference (import statements, etc) to reflect this
move ... correct?I don't think so: as long as your classpath (got from the manifest of the jar) includes the new locations of
these external files.
I think NetBeans works like this: a 'mounted' directory or file is included in the classpath.
ie. when you click 'Compile', NetBeans passes a command to javac, specifying a few different parameters,
and including in the classpath all the mounted files and directories (looks something like:
"javac -classpath .;C:\Programming\Java;C:\Java\ThirdParty\OneWire; etc.", where those directories
specified in the '-classpath' parameter are the mounted directories)
So when you move your app out of NetBeans, all you need to do is to ensure that the required files are
included in the classpath. If you're still working on your app in an editor, you'll need to tell the editor what to
include in the classpath (that's how IDEs make your life easier*).
If you are packaging your app as a jar file, you will need to specify (in relative locations) where your
required files will be located.
Your actual code should not need to be modified.
Does this make sense?
:) lutha
* but, as you can see, they should perhaps only be used when the programmer already understands concepts like classpath! ;-) This is the view of many programmers here on these forums.