I'm programming in Java, and I usually prefer git when programming in Python. So I want to use it for Java too. I'm using Eclipse, but other people may use Netbeans or IntelliJ IDEA or whatever. How is this usually managed when putting Java code into version control?
I'm making a game which uses the library LWJGL, and that library needs to be added to the project file to be used. Therefore, I still need to check the project file into my project.
Short answer, it doesn't matter at all. Create a file called .gitignore in the root of your project file to ignore your IDE's project files or anything like that, then add your code into the git repository. For example, a good Eclipse .gitignore can be found here.
That way the other collaborators won't see your project files, and if they do the same with their .gitignore for their IDE, you won't see theirs.
Related
I have a Maven project. After I make changes to the project, I package the project up into an Uber Jar file and upload that to my backups. I am wondering, if my computer were to break or I lose all the code to the project, can I get the project back using only the Uber Jar file or would the project be gone forever?
How can I open this Jar file as a project and view all the Java code inside of it?
It would be entirely gone; that jar file contains only class files, not your source files, and you can't 'recover' source files from class files (you can decompile them which is mostly useless for this purpose; all comments, most names, most structure - all gone. You can't feasibly continue your project with this).
As it isn't in there, it's not possible to 'open a jar file and see all java code inside it'.
You'll need to set up backups.
The proper way forward is to first set up version control; this ensures that you don't just have a backup of the latest state of your source files, but every state of it - you can travel back to any time. Protects against code you deleted by accident, and means you can freely remove code you think you no longer need without that nagging feeling of: Yeah but what if.... maybe later? - so stop commenting out stuff you don't need, just get rid of it. It also means if there's a bug, you can time travel to the exact point in time when you added the line, and you can review the changes made by others in a project (presumably you're writing this on your own for now, but at some point you'll work with more people than just yourself!)
Read up on git which is the version control system that 80%+ or so of the community uses, probably best not to spring for exotic options if you aren't familiar. There are a billion tutorials out there to find if you search the web.
Host your git on a site like github or bitbucket which therefore also takes care of backups. Alternatively, host it on your own server (it's not complicated; git is open source). If you can't do that either, just let git write to a local directory and then use e.g. backblaze or something similar to ensure that file is backed up.
Yes, you can view your code by using a decompiler. I have experience mostly with IntelliJ, and this IDE includes a decompiler of its own. In case you lose everything and have only the jar file. You can use this included decompiler to get your source back from your .class files. But instructions on doing that are a story for another question...
If you want to secure your code use GIT. A version control tool that is a must when it comes to programming. Google about it and after a few days of playing around with it, you will never worry about such things.
Right-click on your project.
Select Build Path.
Click on Configure Build Path.
Click on Libraries, select Modulepath and select Add External JARs.
Select the jar file from the required folder.
Click and Apply and Ok.
I'm currently working in a big java project with quite a few submodules that are worked on by different teams. Some of these teams are building the "framework", others are building the "application" based on the framework.
When the framework guys move or rename a class, the applications guys get compile errors wherever they are using a refactored framework class. Is there a way in Eclipse (Galileo Release) to record the change and update the references in another workspace?
What I've tried so far is creating a refactoring script during the rename refactoring, but when I try to apply that script to another workspace, it fails with The refactoring 'Rename Type' (org.eclipse.jdt.ui.rename.type) cannot be performed, since its input 'xxx.TestClass" does not exists. Well, it does not exist (anymore) alright, but what I want is for all references for xxx.TestClass in my project to be changed to xxx.MyRenamedTestClass. Is there a way in Eclipse to do this with built-in functionality or an existing plugin or do I have to write one myself?
Thanks for your help!
EDIT: By now I found out that the "Migrate JAR"-Plugin provides the functionality I am looking for, although we build our JARs with Maven, not Eclipse. I'm going through the source code now to find out what parts I can reuse.
Answering my own question to get some closure here.
The easiest way to do it is to use the Migrate JAR File... refactoring which uses a refactoring script in META-INF called REFACTORINGS.XML. You can get a JAR with this included automatically by using Export JAR in Eclipse. We build with Maven and thus just do Refactoring->Create Script... and put it into the appropriate position in the JAR.
The JDT-internal code that Migrate JAR executes creates Stubs for the source classes in a temporary source folder, so it actually executes the refactoring first and then updates the references. The user never gets to see these temporary files.
Alright, so I have a web service that was created using an eclipse dynamic web project. It is currently shared on a CVS repository, but the versioning system used is irrelevant. At the moment, I have literally NEVER been able to pull this project out as is and get it working. It leads to countless errors that cannot be fixed. Every time I need to work on this webservice in a new machine I have to create an entirely new dynamic project, copy over the source files, add all the necessary libraries and make the deployment assembly work correctly again. After finally making it run I share the project as the same one, stop after a second, and then synchronize again (in a way tricking eclipse into thinking this was the shared project all along).
I feel like others must have run into this problem and found a way around it. So if you have a web service or any dynamic web project, what files do you share, and how do you successfully pull it from the repository and get it to run on another machine besides what I currently do now?
Your help is much appreciated,
-Asaf
Edit: After reading some of the responses I feel that this question is actually more specific to those who use WTP to create/test their web services. Just wanted to add the clarification.
Edit2: Let me also clarify that the other 20 or so projects not using WTP are shared just fine. I am able to pull and run them with no problem. Only web service projects are an issue.
In general, you want to check in everything that's not "derived" (generated or compiled - that's usually the contents of the bin directory or other place where your code is compiled/built into). For Eclipse Java projects, you want to include the .project, .classpath, .settings, and any other similar files that Web Tools might create for Dynamic Web projects. The Eclipse CVS client will ignore files marked as Derived so you shouldn't have to worry to much about it.
Without more detail about what kind of problems you've run into, it's not possible to guess what was causing them. My only guess is that perhaps you had different versions of Eclipse and/or the WTP (Web Tools Platform) plugins installed on the different machine. That's just a wild guess, but could explain some incompatibility when you check out the project from CVS.
Bottom line, checking in those .* files is the long recommended approach from Eclipse gurus. Maven can kind of change things, but you didn't mention it so I'm assuming you aren't using it.
I am primarily sharing my experience, may be you can find some help.
Conceptually speaking, the files which the IDE can generate itself while creating new project should not be pushed. I.e the IDE specific files should not be pushed. And everything which the IDE cannot generate on its own must be pushed.
Forexample in case of eclipse, following files should not be pushed:
.settings
build
.classpath
.project
For setting the project on new machine, first pull the files from server, and then create a project from IDE using pulled files.
EDIT: If your project has external jars/libraries, then you will have to add to the classpath manually. You could also push .classpath but that might give errors while creating a new project.
I think it's easiest to use a build system and let the IDE generate the project from your build system.
Eclipse, Netbeans, and Intellij are all pretty good at building projects from maven or ant build files. With this solution you have a simple build that is easy to setup in CI (Hudson, Bamboo, whatever) and you don't have any IDE specific files checked in. If my workspace is totally different than yours, with different versions, plugins, whatever, I'm not stuck with your project file and you're not stuck with mine. My IDE creates the project appropriate for my environment and your IDE does the same for yours.
Since you mentioned having to manually add libraries, I assume you are not using any build manager (like, maven or ant) besides ecplise.
For ecplise to handle the project properly you need the source files (*.java) in their respective directories, any resources bundled with the web service (e.g. services.xml), the ".project", ".classpath", ".settings", etc. files for eclipse. This should be enough for eclipse to generate anything else necessary to build the project.
Any files/directories that are generated by eclipse during the build process (e.g. target & bin directory, *.class, *.war) should not be checked in -- they will be generated when needed during the build.
I am thinking that, since you are adding the necessary 3rd-party jars manually, these libraries might reside in a different path between computers (e.g. if the path contains the username, it will not be transferable to another computer for a different user). To fix that you can set up the classpath using an eclipse classpath variable. In Preferences->Java->Build Path->Classpath Variables set up a varable linked to the "root" folder where the 3rd party jars a stored. Then add the libraries to the project using this new variable, not their full path. To make it work on someone else's computer, you would only need to set this classpath variable to have the build path point to the correct libraries.
It might be beneficial if you migrated your project from eclipse only to a build manager (e.g. maven) that takes care of many of these issues for you. Eclipse can build a project from the configuration of the build manager, making it easier to manage the project.
I was recently given some code that was worked on by someone other than myself, and after lots of work involving hunting down external dependencies, and editing the build.xml file to get ANT to build things in a sane way, I'd like to now get the code into a subversion repository.
The team I'm working on is rather small, but the members on the team change often. So I want people to be able to start working on this code as quickly as possible. A simple checkout from the repository, and opening the project in Netbeans to have everything building and executing properly would be ideal.
How do I achieve this when there are external dependencies that are not going to be on other team members machines?
Should I place the libraries my project uses in the VCS?
How do I instruct subversion to not track generated files such as class files and jar files?
Should binary resources that are unlikely to change such as images and sounds be placed in the VCS? If not what would be the best way to distribute them?
Thank you.
1) yes. Anything needed to build and deploy the application and isn't generated by the build process goes into version control (yah, I know the maven fanz don't like that).
2) make sure everything that's generated goes into distinct directories that you exclude from version control.
3) see 1). Same thing. Same with project documentation, release notes, etc. etc.
The biggest problem of course are directory names which will be set in your IDEs configuration files and differ between development machines.
Not just the location of the project directories, but the IDE itself, JDKs and other tools, appservers, can all be different between machines. It's a constant problem.
I usually use maven cause you can have a repository for jars and dependencies this makes life easier, but since you have already refactor your code to use ANT maybe this is not what you want, to use subversion with netbeans then you might want to add another folder for jars like libs or something and then another for the binaries like audio etc. Also check for the svn plugin for netbeans it will add the ignore to the dir and just update java files.
To add files to ignore you can use
svn propset svn:ignore -F .
or you can look for the config file in your subversion home and add something like this
global-ignores=*.classs
Hope this helps
I am working on buid a plugin of Eclipse. In one step, i load the project through scan classpath,but the feedback from requirement is:
Loading projects encompasses two things:
Loading multiple files from the same
directory/package
Including files from other packages through for instance Eclipse's .classpath files
Since the prototype will be built into an Eclipse plugin anyways, is it fine to use Eclipse stuff, like the .classpath files? you are now loading and reading these files yourself. It might be more convenient to use Eclipse code for this, since it has to be already there.
I have no idea how to deal with it from Eclipse, can anybody help?
I think you're looking for PDE build. You could have a look at this tutorial.