How to build and run Maven projects after importing into Eclipse IDE

Question

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?

Answer 1

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.

Answer 2

Dependencies can be updated by using "Maven --> Update Project.." in Eclipse using m2e plugin, after pom.xml file modification.

Answer 3

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)

Answer 4

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 5

answer 1

1. Right click on your project in eclipse
2. 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

Answer 6

1. Right Click on your project
2. Go to Maven>Update Project
3. Check the Force Update of Snapshots/Releases Checkbox
4. Click Ok

That's all. You can see progression of build in left below corner.

Answer 7

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.

Answer 8

    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>

Answer 9

Run the maven build once and should be gone