I was looking for information about mvn eclipse:eclipse and I realize that there are some obsolete goals here, one of them is eclipse:eclipse.
Is there any alternative to doing the same from the command line?
This plugin is deprecated, there's no need to use it anymore. In fact, it will do more harm than good.
In short: eclipse:eclipse generates all eclipse files based on the pom.xml. This means that if you change the pom, you always need the run the goal again. With m2eclipse it is aware of changes in the pom and will update your project on the fly in most cases. I know that if you update the source/target, you need to run a Maven Update from the context menu explicitly.
Related
I want to create a Maven Project through command prompt. I have installed Eclipse+Maven.How to find out the location of mvn folder?
The Maven that is included in Eclipse cannot be used on the command line.
You need to install a separate command line Maven for that.
I think it's best if you provide more details of exactly what you want or need to do. When you say you want to create a maven project through the command prompt, do you mean with a maven archetype? I have a feeling you don't know what that is.
If you want to create a new Maven project, you can do it in Eclipse, with "File"->"New"->"Other..."->(filter for Maven)->"MavenProject".
In my maven project I usually use the POM file named pom.xml. I have a second POM file though (call it pom_alt.xml), which I occasionally use to perform a very different build of the same project. To do so I specify the -f option in the command line
mvn clean package -fpom_alt.xml
as suggested by man mvn:
-f,--file
Force the use of an alternate POM file.
Now, when I am coding in eclipse I usually need maven to use pom.xml, but sometimes I should code or debug while the other file pom_alt.xml is used instead. Is there a way to tell the eclipse maven integration to use that file? Currently I am temporarily copy-pasting from pom_alt.xml to pom.xml since I seldom happen to need that, but you can see that's not optimal.
I am with Eclipse IDE for Java EE Developers, Mars Release 4.5.0.
UPDATE
I could build from the command line or use Run As Maven build as in
Carlos Andres' solution, but ideally I would like to define a persistent setting, like a property or preference. This because I find nice if the POM file can be fixed while I am doing things like running as Java Application and test cases, or executing on a server. Processes that require a project clean or server restart are often triggering a maven build with the default POM.
Check that M2E - Maven Integration for Eclipse is installed on Eclipse. Once that is installed go to the project and press right click
Next, put the command that you want to execute
This option allow you to save the commands, and the next time all your commands will be saved.
To execute the command recorded go to
I’m using Eclipse Mars with Maven (v 3.3). When I update a dependency in my pom (change the version), my Eclipse-Maven project doesn’t pick it up, even when I right click my project, and select “Maven” -> “Update Project.” I know this because I do not see compilation errors in the Eclipse Java editor that I see when I build the project on the command line using
mvn clean install
When I remove the project from the workspace and re-import it, then things get back to normal. However this is a cumbersome process. How do I get my Maven-Eclipse project to automatically detect changes in my pom and update the project libraries appropriately?
And yes, in the “Project” menu, “Build Automatically” is checked.
When you import the project into Eclipse, use Eclipse's own built-in Maven support (aka, m2e). I recommend against using mvn eclipse:eclipse as it doesn't give the best results (as you're seeing). Maven is a build and dependency management tool, not an IDE; expecting it to manage IDE-specific stuff is silly, in my opinion (I realize the Maven team thinks differently, that Maven should be responsible for managing your IDE, but that's nonsense).
So if you have the project available on your system, delete any Eclipse-specific files (typically just .classpath, .project, and folder .settings), they were generated by mvn eclipse:eclipse and you don't want them interfering with the "proper" import process described here. Then inside Eclipse, use File > Import > Maven > Existing Maven Projects to import the project. That should result in better integration between Eclipse and maven, including automatically updating the Eclipse build path when the pom is changed.
As a quick check, after doing the import that way, you should see a group called Maven Dependencies in the Libraries tab of the project's Build Path (in Properties dialog). Like this:
If you want the Eclipse project configuration to be automatically updated every time the pom is changed, there's a (experimental) setting for that under Preferences > Maven. Be aware that doing so might not be desirable, though - as mentioned in this feature request, it's a somewhat lengthy process that touches a bunch of stuff in the Eclipse Project; doing that automatically on every pom.xml change could end up being more trouble than it's worth.
Three Mandatory checks you should do for automatic update in your classpath
Your Repository is not in-sync with your Eclipse IDE, Please check the below settings in your IDE.
Right Click your any POM.xml from your IDE and check for the Maven profile which should be auto-activated. Also offline and Force update check box shouldn't be enabled. Please refer the below image.
Always check for your user settings which should reflect your local maven settings.xml, as shown in the below figure.
After performing all these checks, refresh your Eclipse Work-space to get these changes reflected.
Eclipse should be updating your classpath. If it's not, that implies something is going wrong.
It's hard to say what the problem could be exactly without knowing more about your project's pom.xml. More information might be necessary to solve the issue, but I'll just make a stab in the dark:
Open the .project file in your project's root folder and check the ordering of builders and natures there. It might be possible that some other nature on the project is also causing maven2Nature to fail. Move maven nature up and see if that helps any.
Alternatively you might be thinking that Eclipse does not update your dependencies because it does not add some some error indicators in the project that should be there with new dependencies. If that's the case try cleaning the current project (project>clean...). Maven in Eclipse does not necessarily trigger a full rebuild when dependencies are updated.
If none of this works, closing/opening the project might solve the issue quicker than re-importing.
What you wrote, should work. Did you check this:
does "pure" mvn install from terminal see your changes in POM?
maybe some Maybe plugin is buggy, cached some dependencies in target, and mvn clean install is needed
you can run Eclipse in a new workspace, and import your project there, sometimes it helps in case of such strange problems
instead of importing Maven project to Eclipse via m2eclipse, you can try to create Eclipse files via the old mvn eclipse:eclipse and see what happens then
does it work well when you try to import your Maven project to other IDE, the free IntelliJ Community Edition for example?
As a last resort, you can delete your current Eclipse installation and install a new version. When you add several plugins, they might interfere with one another and create weird behavior. After you do that, do not import your Maven project into your workspace, but rather create a new one and copy and paste the files that you had.
I thought I understood Maven as I've worked on a few projects using it, but I seem to be having trouble creating my own project with it, so can someone correct me wherever I may be wrong?
Assuming I create a new Maven project (we'll say I did it through Eclipse or IntelliJ):
If I add a dependency to my POM file, assuming I add a public repository where that dependency can be found, shouldn't the IDE download the specified JAR and make it so that it is recognized when I use it in my code? Currently, my projects do not recognize any classes that should be found in JARs via my POM dependencies.
Assuming #1 does work, how can I determine via maven which transient dependencies I have? For example, I'm using classes from Pentaho Data Integration, and some of the plugins for it reference things like org.mozilla.javascript.*. Could maven automatically tell me that without me having to run the code, see it fail, and manually fix the dependency? There will be hundreds of those instances here, so manual fixing really isn't viable.
Here are my IntelliJ two cents:
1 - Adding a dependency in pom.xml of your project
Should indeed download the depended jar(s). You may need to approve "Import Changes" dialog if it pops in, or enable auto import.
2 - Seeing transitive dependencies
It can be achieved via Maven Dependencies Diagram - unfortunately only in IntelliJ Ultimate edition. You can use Maven Dependencies Plugin to see the dependencies tree in your favorite CLI.
Question 1: Adding a dependency
In Eclipse, depending on how you created the project, you should be able to add dependencies that are automatically recognized using the maven context menu.
Note that you should have created the project using the eclipse maven plugin so that it has maven nature.
To add dependencies/plugins from a remote repository, you can search in the resulting UI for a dependency if you know the artifactId or groupId. The plugin will pull up the deps whether the repo url is specified in the pom.xml or not.
After adding a dependency to the POM, the IDE will start downloading it and all transient dependencies as soon as you save the file.
If something goes wrong, you can try to "Update Project" from the context menu.
Question 2: Determining transitive dependencies
Transient dependencies are visible in the "Dependency Hierarchy" tab of the POM editor.
I usually default to the command line because it allows much more flexibility and functionality when tracking the dependency graph.
I am sorry but I have not worked with IntelliJ
Note: I'm asking about the command line mvn tool, although I imagine similar answers would apply to the m2eclipse plugin?
It's a bit confusing what the command line mvn targets that mention Eclipse actually do and DON'T do.
Confirming what I believe I understand:
The mvn eclipse:eclipse command is just generating Eclipse dot-project files? You would them import them into Eclipse?
The -Declipse.workspace=(eclipse-workspace-path) eclipse:add-maven-repo is just updating workspace files to point a repository, but does not tell the workspace anything about your maven projects, even if you do both steps in the same command?
When I first saw the references to Eclipse in the Maven doc I thought perhaps you could generate set of Eclipse projects and add them to a template workspace from the command line, but I guess that was just wisshfull thinking.
The m2eclipse and command line mvn tool take two very different approaches to Eclipse/Maven integration. It sounds like your question is about mvn tool.
The mvn eclipse:eclipse command reads your pom file and creates Eclipse projects with correct metadata so that Eclipse will understand project types, relationships, classpath, etc. It does not actually import those projects into a workspace as creating a workspace or importing projects into a workspace requires running Eclipse. You have to re-run this command when anything in your pom changes. Once you run this command, it is simple to import the created projects into your workspace. Just start Eclipse and use File -> Import -> Existing Projects wizard. Once you've imported projects you will not have to repeat this process after re-generating metadata unless the number of projects have changes. Just start Eclipse back up, select all projects and invoke refresh from the context menu.