I'm using eclipse with the m2eclipse plugin now I just want to resolve a - imho - easy problem: I've got two maven projects, I want to add project A as dependency to project B.
Well how do I achieve this in a manner way? If I add the project A to the build path of project B eclipse recognizes the classes but this project isn't resolved by eclipse on build time.
I got it working by installing project A to my local repo and adding this as dependency to my pom. This works but is cumbersome because I always have to install a new version of project A when something changed.
Shouldn't the plugin handle such a situation for me?
Providing that you have both maven projects open in your workbench then make sure you have the "Enable Workspace Resolution" option enabled in the Maven context menu.
Yes Eclipse handle this situations.
You can add both the Projects A and B in the same work-space.
I could help you creating a simple work-space from the scratch.
I am assuming that you have already installed the MAVEN plugin M2Eclipse for Eclipse.
Start a new Eclipse in a blank Work-space
Right click on Project Explorer --> Go to Import dialog and add a Maven Module.
Locate the POM directory and add that directory.
It will list all the projects in all the sub folders.
Add as many as Maven Based modules in a single work-space.
By doing this you dont need to install the dependencies. Any change will be reflected on the derived module.
Hope that will help you.
The way you did it is correct, because it assumes that project B will be using the dependency of project A that will be in the artifactory, so you can develop both independently.
And anyway, for the project A, if you are using maven, don't you use maven clean install for compiling and deploying? That way you are sure you always have the latest version
The other option is, in case both of the are more dependent of each other, you should consider make one of them as a module of the other, or maybe make a project C that contains both modules, but that would mean both of them are part of the same project (like an ear containing two jars), depends on the situation
Related
I've got a couple of java projects that depend on the same piece of code. Lets call them:
Project A
Project B
ComponentX.java
The projects are set up like this:
Project A > ComponentX.java
Project B > ComponentX.JAR
This set up where Project B contains ComponentX's jar file is inconvenient. Any time I make a change to ComponentX.java, I need to remember to export the Jar to Project B. It also makes debugging Project B difficult. There has to be a better way, I just don't know what to google. I'm using Eclipse. I use Maven so any solution using that would be Ok, although I'm hoping that there is a simple Eclipse based solution.
I'm guessing I'll need to move componentX into its own project and somehow make the other two depend on it.
You most likely want to create a new library project that will be used by both Project A and Project B as a standard Maven <dependency>.
There are few guides available online. If your projects are all part of the same multi-module Maven build you can take a look at Creating a Multi Module Project guide on spring.io.
So I had a lightbulb moment. Any maven project can be imported into any other maven project the exact same way you'd import any other dependency. Seems obvious now but I've only ever imported libraries other people wrote.
So if you've got three projects:
WebApp
DesktopApp
Dependency
Where both WebApp and Desktop need to reference Dependency. This could also apply in a case where there is repeated code in two projects, just pull that out into it's own project and remove it from both.
Simply make Dependency project a Maven project by right clicking > Configure > Convert to Maven Project. You'll get a .pom file with something like this at the top:
<groupId>Dependency</groupId>
<artifactId>Dependency</artifactId>
<version>0.0.1-SNAPSHOT</version>
Then all you have to do is add that as a dependency to any other project's .pom that needs access to it:
<dependency>
<groupId>Dependency</groupId>
<artifactId>Dependency</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
That's it
I have added all the jar modules I need for my project in a folder called 'libs'. I right click 'Add as library' and the module is implemented and will work for the duration of that build.
My problem is that whenever I rebuild the project in anyway it 'forgets' about these modules and I have to re add them over and over.
What am I doing wrong?
EDIT: I forgot to mention that I am using gradle
Any IDEA version from about 12 up (current version 15 is superb) should handle maven projects correctly.
Make yourself a pom.xml and put at the root of your project.
The <dependencies> section defines your libraries (they must have their own pom.xml).
IntelliJ will automatically sync the libraries in your project whenever you make changes to the pom.xml. Thus you avoid having to add or remove modules manually any more.
You can either run your java code as normally, or run a maven goal such as install from the maven pane on the top right.
Hope this helps! Once you start using maven (or an equivalent tool like gradle) your life with multiple dependencies will get much easier.
I have a project that devided into three pieces, PCommon, PWebapp and PAdminConsole. PWebapp and PAdminConsole are dynamic web project in eclipse, PCommon is java project, and both two web project will use the api in PCommon as a jar file in lib folder.
In the past,I added import project in build path, I used Ant to compile and build PWebapp and PAdminConsole and in both build.xml file there is
<ant antfile="${common}/../build.xml" inheritAll="false"></ant>
to make PCommon into a jar file.
Now I will change all my projects to Maven Project. But I don't know how to make two web projects contain one public module, and how to package my PCommon into a jar file automaticlly when I run package maven command to package one web project.
Now I always deploy my PCommon.jar on nexus server. and then add dependcy in pom.xml in web projects. But I think there is no sense to deploy the jar on the public server, so I think it isn't the right way to archieve this goal. Is there any way that is more convenient?
I know I can make a parent project with a parent pom.xml. But I have two web project need the module, the pom.xml in PCommon can only extends one parent, can't it?
The common way to resolve dependencies in Maven is using a repository. The first time a dependency is needed, it is downloaded from your repository and installed in the repository on your local machine. If a dependency is not available in the remote repository it has to be installed to your local one in some other way. There are a few other ways to resolve depenencies without using the repositories but I wouldn't suggest to use the.
To make this a little more convenient, you can use a proper IDE. I use Eclipse with the m2e plugin. It supports something called "workspace resolution", which should be enabled by default. It scans your workspace for other Maven projects before falling back to the repository lookup. This has the advantage that every change you make in your common project is immediatly available in the other projects. I think it also gets installed to your local repository in the background but I'm not sure. Anyway you don't have to worry about it yourself.
Something similar works with IntelliJ IDEA but I don't have that much experience with it. I'm sure Netbeans has some kind of Maven support too.
If i want to convert an EAR project a maven project , do i need to add the module in the deployment assembly as maven dependency or just use the convert in m2eclipse without any further configuration.
Me personally I wouldn't attempt any kind of conversion of an existing project. I would add the poms, make sure that mvn clean install works on the command prompt and then create a new mavenized Eclipse project from the poms.
The main reason is that you current project settings are effectively wrong when you switch to Maven - the Maven poms are the truth and what feeds the Eclipse project setup, so you really do not want to make your life difficult and work against m2eclipse - let it do the project creation for you. Fresh.
You can install m2eclipse and then do the following as well.
Go to the project menu (right click on Package Explorer) > Configure > Convert to Maven Project
Open the pom.xml and right-click and choose Run As -> Maven Clean. Similarly Choose Run As -> Maven Install.
Note : Please ensure that your eclipse project settings are correct and classpath libraries are not absolute and you don't have any project specific environment variables defined in your workspace. Please take a backup of your project before you do this.This is to ensure we don't mess up the current stable project configurations. Once m2eclipse generates the pom.xml for your project, you can update and make changes to it to
fully obtain a mavenized ear build. hope this helps
You can also try creating new maven project with archetype selection of "jboss-javaee6-ear" and follow the similar structure for your project. Most probably you will need parent Pom and child poms per each module (ejb, war, jar etc). There are other few similar approach but almost all of them requires you to have mulitple POMs
maven-ear-plugin and JBoss AS 7
You can also go through all the examples for maven ear plugin to find settings suitable for you
http://maven.apache.org/plugins/maven-ear-plugin/
I ended up ditching ear for war :) single POM and even ditched the JBOss for tomcat/jetty :)
If you want to convert your existing eclipse dependencies into Maven dependencies, you can try the JBoss Tools (JBT) Maven integration feature, which contains an experimental conversion wizard, plugged into m2e's conversion process : http://docs.jboss.org/tools/whatsnew/maven/maven-news-4.0.0.Beta1.html.
So, all you have to do is, as Keerthi explained, right-click on your project and Configure > Convert to Maven...
If your dependencies already are maven artifacts, it should work easily. If not, you'll need to convert them to Maven (if they're workspace projects) or make them available in your maven enterprise repository, before converting the EAR project.
JBT (requires Eclipse JavaEE) can be installed from http://download.jboss.org/jbosstools/updates/stable/kepler/ or from the Eclipse Marketplace (See https://marketplace.eclipse.org/search/site/jboss%2520tools)
I found an annoying issue working with m2eclipse in Eclipse.
My workspace contains 2 projects, an application A and a library B. The application A POM has B as a dependency and everything works correctly. (The project dependecy is found and used when I build the application)
But if I change some code in project B and I forgot to mvn:install it, when I build the application it uses the last built version of the library and it loses my last changes.
Is there a way to force Maven / M2Eclipse to check if the source code of the dependecy is newer than the last version built, and to install it when installing/ deploying the main application?
Or maybe my approach is wrong or is something obvious that I'm missing?
You can tell m2eclipse to use resolve dependencies from the workspace rather than through the normal mechanisms. In your project properties (NOT workspace properties), select Maven->Resolve dependencies from Workspace projects.
This will mean that when you change B and subsequently build A, the changes should be picked up automatically.
If, however, you build outside Eclipse, you'll have to do the normal mvn install to get the correct dependencies.
I don't know of a way to tell maven to build the library first, then build your project. You could put two maven commands into a script and run the script.
Alternatively, you could put both projects inside a maven parent project, and then build the parent. This causes all child project to be built too (so in your case the library, and the application).
I think you have couple of options here
If you can change the maven project set up, I would suggest you to use maven multimodule
Option two might solve your problem but still involves a manual stop when you change your dependent project B, Do this on for your dependent project in eclipse
Select Library B ==> Properties ==> Maven ==> in the input box under Goals to invoke after project clean: ==> enter : install
To deploy any change that you made to Project B in eclipse to maven local/remote repo, You have to run Clean build in eclipse, This will deploy the latest Library B to the maven repository
Also make sure your Library B version is a SnapShot during the development
If you are looking to run the latest snapshots on your local machine you should try to set things up to launch directly from Eclipse.
Apart from avoiding the problem you originally posted about, it also has other advantages.
It will save you a lot of time by not having to perform intermediate build steps.
You can start and stop servers without having to leave your IDE.
The Eclipse console has extra features that you don't get from the system console.
You don't have to modify your start scripts to attach a debugger.