I have developed an Java application with RMI,JPA and H2DB, look at the screenshot is my project :
All I need is to have two JARs (client and server) with imports to the libraries described in the screenshot.
the problem is that netbeans does not generate two JARs for the same project :
this box allows you to create a single jar for the project...
is there a solution for this problem?
thans in advance.
If you want to keep your project structure, I would suggest using an ant script to build your jars. That way you can specify which source files and jar dependencies to include in your client and server jars.
Break up your project into three modules. One for shared code, one for server and one for client. Having it all together like you have will eventually result in unmaintainable code (and sooner rather than later..).
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I have a project with a library JAR and a set of applications. Right now the applications (all 5 of them) are in a single project. These tools each have one or two classes, they run from the command line with one exception. Even the GUI tool has only about 8 classes. I am struggling with how best to structure this in Eclipse.
I have seen that I can use maven-shade to create multiple executable JARs from one project. I would need to convert the project to Maven, but I assume that is not a big problem.
I can create a separate project for each tool. This seems like overkill to have several projects with one or two classes in each.
Additionally, both of these solutions will leave me with either a bare class file or a JAR plus the dependent library JAR. Not ideal for deployment.
Before I pick one of these, I thought I would ask here if there is a different approach that I am missing for packaging these tools.
In eclipse, Export --> Archive file, You can select/deselect what classes you want to export into your Jar File
Yes, but You could/need to create using Maven, and for each build building jar you need to set the main Class.
Checkout the documentation of Maven.
I think You could to the same with Gradle, but not sure.
https://maven.apache.org/plugins/maven-jar-plugin/examples/attached-jar.html
When I clean and build, Netbeans generates a .jar file for my Java project, and it uses a "lib" folder which has all of my external Jar files that I use. Can I somehow tell Netbeans to package these Jar files into the .jar it makes? So that I can run my project as a stand-alone .jar file?
I am using Netbeans 7.1.1 on Mac OSX
The short answer is no, the long answer is complicated.
Firstly, Java does not support embedded Jars (ie, you cann't simply add the depended Jars into the main Jar).
Secondly, uncompressing all the Jars and merging them into one will overwrite any resources/classes that share the same path/name. This may not be an issue in small projects but is a major issue in large ones (we have this problem with the project I'm working on at work).
One solution is to use something like One-Jar, which basically uses it's own boot class loader to all you to reference Jars inbedded within a single Jar.
I've had issues with this when using our own custom classloader, but otherwise it seems to work well.
It includes Ant support, so you can include it in your projects Ant build script, if you not using Maven, otherwise, you'll need to devise your own build process
There is no options in netbeans to do that.
There are some other options that a quick search would help, but requires manual intervention.
I keep server and client code in the same project of Eclipse. Libraries for both of them are included. Images for the client are also added to the build path.
Now I want to generate jars for server and client, that they include only required libraries, and server jar does not have images included.
Is there a way to do this without maven, etc?
Right-click on the project and go to Export. Select jar from the selection tree and in the next tab, remove the code/resources that you don't want included in the jar. Better still if you keep them in separate projects (even if there is no client java code, you can create a resource project).
However, what you're describing sounds a lot like a WAR file. Contrary to a jar, a WAR file is a deployable jar meant to be added to a web hosting application like Tomcat. I don't know if that's suitable for your needs, but more often than not, you want to have both server and client code together. If your project is dependent upon another project, that project will automatically create a jar that will be included in the WAR.
You can divide your sources into three source (and output) folders within the same project:
src-shared
src-server
src-client
Then create a build.xml (Ant buildfile) which creates a jar from bin-shared + bin-server and a jar from bin-shared + bin-client.
Note: One danger of keeping it in the same project is that you can accidentally use client classes from server classes, or vice versa, which will fail at runtime. To fix this, make three projects instead of three source folders.
So I'm fairly new to Java and especially Eclipse, so please excuse my ignorance. I took a project from a server and copied it locally to my machine. When I opened the workspace, I had many errors due to it not being able to find the jars. This makes sense because I don't have the same dir structure as the server I copied from. So if I copy the same external jar's to my machine and get it to compile into a jar and copy it back to the server, will it work? Or will it fail because now the external jar's are in a different place than it is expecting?
Also, down the road should I put the external jars into regular jars to avoid this problem?
You should be OK. Java is using what is called classpath to locate dependencies. The classpath may be different on the development machines, but as long as all the dependencies are on the classpath in the production everything should work.
To avoid issues with the synchronisation of directory structures the most common way is to use Maven - it will manage all the dependencies for you (but you have to manage the pom.xml - the Maven's project descriptor). A little clumsier way is to have the dependencies in the project, however you may end up with many projects having to include same jars, and then there will be version conflicts and so on.
For small projects you can manage dependencies yourself, however larger projects will need a more thought through strategy (like Maven).
In regard to the executable jars, make sure the Class-Path entry in <jarfile>:\META-INF\MANIFEST.MF is correct, e.g. where it references other jars, those jars are going to be there in the production. For example, assume we have ourjar.jar and assume this is a snippet from its MANIFEST.MF:
Class-Path: lib/myteamjar.jar
It will then be expected that a following directory structure is in place:
lib/myteamjar.jar
ourjar.jar
No, the location of the external jars does not mater. What you want to do is put the external jars on your classpath. How you do it depends on how you are running your java code. If you are running it from the CLI using the java command, it takes the classpath as an argument. If you want your code to build/run in Eclipse, you need to right click on your project, select "Build Path" > "Configure Build Path..." Use the "Add JARs..." button to add jars that are part of a project you have open and "Add External JARs..." to add jars that reside outside of the project. See specific documentation for your tool for more details about classpaths.
I would not recommend Maven to somebody who is fairly new to Java and Eclipse. I would forget about Eclipse, too.
You have a packaging and CLASSPATH issue. Focus on that.
What kind of project are you talking about? The answer you get will depend on what type of app you're creating. Is it an executable JAR? Then the right way to do it is to package everything into a ZIP file that's laid out exactly as the CLASSPATH in the JAR manifest expects.
If it's a web app, the right thing is a WAR file, with all the JARs your app needs in the WEB-INF/lib directory.
If you package things properly, you should end up with a single package that has everything laid out the right way. You should be able to deploy it to the server and make it all work.
I'm using some apache libraries in my code. At the moment I'm hitting a variety of problems that I need to debug. However the problem is when I pass data into one of said Apache libraries, when I try to step into the method call using netbeans it simply does the processing in the background and doesn't step into the code I want to view.
Does anyone know how I configure the IDE so that I can debug the apache code as well? Right now I just associate the JAR's with the project by adding them as libraries.
You need to attach a source jar (e.g. commons-lang-2.4-sources.jar) to your dependency, instructions here
I should also recommend using Maven2 to manage your project dependencies, I've not used Netbeans for at least 5 years, but both Eclipse & IntelliJ have Maven plugins which will import all your dependencies and link them to sources/javadoc jars automatically.