I imported a Maven project into Eclipse. I was able to deploy it from the command line. In Eclipse it is full of red Xs. I have cleaned the project, updated the configuration and I ran the following command:
mvn -Declipse.workspace=<pathtoworksapce> eclipse:add-maven-repo
and I still have the same problem. The project is dependent on another project.
What I ended up doing was removing all of the projects in Eclipse, but not deleting the source files. Then instead of directly importing the code as Maven->Check out as Maven Projects with SCM, I selected Existing Maven Project and imported the code from my local machine. This got rid of the errors, but when I would right click on code and select "Open Declaration", I would get Error: Could not open the editor: The file does not exist" So I removed all projects again and this time I deleted all the ".project" files and repeated the import Existing Maven Project. So now there are no red Xs (dependency problems) and the lookup functionality within the code works.
Go to your master project and type the following :
mvn install
mvn eclipse:eclipse
After that, import your project. You can also install m2eclipse for better support. If you use gwt or any other framework which has a custom maven execution, you should also install plugins for those in Eclipse.
Related
I have an existing maven project which I downloaded from GitHub.
If I run mvn clean install from the root of the project everything works fine (a jar file is created in target folder and it executes works OK).
But when I go to Eclipse and import this project as Existing maven project I get multiple (395 to be precise) Java Problem errors (like The method is undefined etc.).
The only thing that I notice is when I run maven from command line it creates .m2 folder inside the project folder while maven from Eclipse creates .m2 inside my C:\Users\username folder.
I'm using Eclipse 2019-06, Java 8 and apache-maven-3.6.1.
P.S. Same errors appear when I import this project to Intellij IDEA 2019.2.
Olga, don't worry. Import the project into Eclipse. Then wait some minutes. If the errors do not vanish, try "ALT + F5". If this still does not help, build the project from within Eclipse ("Run As -> Maven build"), do "ALT + F5" again.
Eclipse often takes some time to fully "understand" the project, i.e. synchronise the POM and the files to its internal mechanisms.
In Eclipse Neon, I did an 'import existing maven project' from a local folder, whose content was copied from another machine. The project is not reading the dependencies on the POM file, and one example is the log4j dependency. A workaround is to add the log4j-1.2.17.jar manually to the project as an external jar, but this is wrong. Does anyone have tips on how to troubleshoot? I am fairly inexperienced with maven so I m not sure if there are additional settings or configuration that I have do when importing an existing project into eclipse.
You can make sure if your project dependencies are being pulled correctly or not by executing
mvn clean install
from within the project directory on the command line. This would download the required dependencies of the project as well.
The most common cause I have seen for this issue occurs whenever Maven encountered an error while downloading an artifact from a repository. In this case, Maven marks the download as failed and won't retry until some time elapses (I do not remember how long).
The easiest way to test this is to delete the .m2/repository folder in your home directory and let Maven download the artifacts again. If you have Maven installed you just execute "mvn install" from a console. Otherwise, you can try:
Right click the project in Eclipse
Select "Maven > Update Project"
Check "Force Update of Snapshots/Releases"
Click "OK"
I checked out an existing eclipse project from SVN. Then I converted it to Maven project.
The project is compile with Maven target clean install perfectly no problem. But the eclipse doesn't identify any dependency jar file. Basically it does not know the Maven repo path. It knows only JDK path. So all my java classes are with full of red lines.
Everything in this site and google I checked all fine. But why eclipse can not find the mvn repo?
eclipse version = JUNO Version: 4.2.2. ( I think this has inbuilt maven plugin)
Maven plugin detail = M2E - Maven Integration for Eclipse version - 1.4.0, Provider - Eclipse.org -m2e
UPDATE ======================
If I checkout the source code separately and import it as a maven project that way its working. But I want to know why if I checkout the code through Subclipse and convert it to maven project is not working?
Run
# use maven to control your eclipse .project and .classpath files, that is
mvn eclipse:clean
mvn eclipse:eclipse
and then restart your eclipse (or switch your workspace and then back).
Make sure you have the m2e plugin, - from here, you should read the Release Notes and add this to your update sites - "http://download.eclipse.org/releases/juno" and "http://download.eclipse.org/technology/m2e/releases".
In Eclipse, you can actually create an external tool Run> External Tools> External Tools Configurations. After this you can select your project that you want to setup and run this external tool.
or if you have maven plugin installed in eclipse, select your project right click Run As > Maven Build... (see below image). In Goals put "eclipse:eclipse" and click Run
I am learning building a Java project in Eclipse using Maven. I created a Java project HelloWorld from
“maven-archetype-quickstart” template in a folder D:/maven_projects. Then to convert the Maven project to support Eclipse IDE, I navigated into the project folder and issued the commands:
mvn eclipse:eclipse and mvn package .
Then I imported the project in Eclipse and did the necessary Eclipse configurations like setting the Maven local repository in Eclipse classpath. Now the project in D:/EclipseWorkspace folder. I ran the project successfully in Eclipse printing "helloworld".
Now if I want to go on develop the project and for that reason want to add new dependencies in pom.xml in Eclipse, then the new jars are not added in classpath when I run the project.
So my question is after importing a Maven project into Eclipse how can I add more and more dependencies in pom.xml, then build and run the project? What is the recommended and efficient way to do this?
I would recommend you don't use the m2eclipse command line tools (i.e. mvn eclipse:eclipse) and instead use the built-in Maven support, known as m2e.
Delete your project from Eclipse, then run mvn eclipse:clean on your project to remove the m2eclipse project data. Finally, with a modern version of Eclipse, just do "Import > Maven > Existing project into workspace..." and select your pom.xml.
M2e will automatically manage your dependencies and download them as required. It also supports Maven builds through a new "Run as Maven build..." interface. It's rather nifty.
1.Update project
Right Click on your project maven > update project
2.Build project
Right Click on your project again. run as > Maven build
If you have not created a “Run configuration” yet, it will open a new configuration with some auto filled values.
You can change the name. "Base directory" will be a auto filled value for you. Keep it as it is. Give maven command to ”Goals” fields.
i.e, “clean install” for building purpose
Click apply
Click run.
3.Run project on tomcat
Right Click on your project again. run as > Run-Configuration.
It will open Run-Configuration window for you.
Right Click on “Maven Build” from the right side column and Select “New”.
It will open a blank configuration for you.
Change the name as you want. For the base directory field you can choose values using 3 buttons(workspace,FileSystem,Variables). You can also copy and paste the auto generated value from previously created Run-configuration. Give the Goals as “tomcat:run”. Click apply. Click run.
If you want to get more clear idea with snapshots use the following link.
Build and Run Maven project in Eclipse
(I hope this answer will help someone come after the topic of the question)
Dependencies can be updated by using "Maven --> Update Project.." in Eclipse using m2e plugin, after pom.xml file modification.
Just install the m2e plugin for Eclipse. Then a new command in Eclipse's Import statement will be added called "Import existing maven projects".
answer 1
Right click on your project in eclipse
go to maven -> Update Project
answer 2
simply press Alt+F5
after updating your pom.xml. This will build your project again and download all jar files
Right Click on your project
Go to Maven>Update Project
Check the Force Update of Snapshots/Releases Checkbox
Click Ok
That's all. You can see progression of build in left below corner.
When you add dependency in pom.xml , do a maven clean , and then maven build , it will add the jars into you project.
You can search dependency artifacts at http://mvnrepository.com/
And if it doesn't add jars it should give you errors which will mean that it is not able to fetch the jar, that could be due to broken repository or connection problems.
Well sometimes if it is one or two jars, better download them and add to build path , but with a lot of dependencies use maven.
If you are getting this error :in cucumber Exception
Cucumber Exception: java.lang.ClassNotFoundException:
cucumber.io.ResourceLoader :
then add following jar file to your pom.xml
<dependency>
<groupId>info.cukes</groupId>
<artifactId>cucumber-core</artifactId>
<version>1.1.8</version>
</dependency>
Run the maven build once and should be gone
I've got project with a few sub modules.
mvn clean install
works absolutely fine. But in Eclipse with the parent project open none of the maven dependencies are available and so all my Java source files are full of indicated compilation errors (they're not listed in the build path for the project). If I open one of the sub modules as a project there are no indicated compilation problems.
I've tried running
mvn clean install eclipse:clean eclipse:m2eclipsemvn clean install eclipse:clean eclipse:m2eclipse
and choosing project / update maven dependencies. Refreshing, closing and opening the project and Eclipse, etc.
Any ideas? Thanks in advance.
Getting m2eclipse to match maven's classpath
Just use Import... > Existing Maven Projects and import your multi-modules Maven project, that's all.
But in Eclipse with the parent project open none of the maven dependencies are available and so all my Java source files are full of indicated compilation errors (they're not listed in the build path for the project).
A parent project (i.e. with a pom packaging) is not a Java project, it's just there as a facility to make editing the parent pom.xml from the IDE possible (and that's already nice, importing nested projects inside Eclipse was initially not even possible).
If I open one of the sub modules as a project there are no indicated compilation problems.
That's how you are supposed to do things.
I've tried running (...)
You are not supposed to use the Maven Eclipse Plugin when using m2eclipse and this is not supported. Either use one or the other. If you decide to use m2eclipse, use Import... > Existing Maven Projects as suggested.