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Import library in Java project via

I was looking for a Random name generator and found https://github.com/DiUS/java-faker on GitHub. There it says:
In pom.xml, add the following XML stanza between <dependencies> ... </dependencies>
<dependency>
<groupId>com.github.javafaker</groupId>
<artifactId>javafaker</artifactId>
<version>0.16</version>
</dependency>"
I am not familiar with Maven or Gradle or how it works, nor did the documentation of Maven really help me with importing this library into my Java project in Eclipse.
Would be thankful for any guidance (links) towards the documentation/info I need in order to understand how to use this library via either Maven or Gradle. Is this actually that complicated? Why can I not just download and add the library to my build path?

Gradle
Make sure you have Gradle installed by running gradle -version.
Create a directory for your project and navigate into it. Open a terminal.
Execute gradle wrapper. You'll see gradlew and gradlew.bat files and gradle and .gradle directories created. From now on, you can forget about global Gradle installation as you can use wrapper. Wrapper can be used even when Gradle is not installed.
Create a file named build.gradle. It's a project descriptor in Gradle:
plugins {
id 'java'
}
repositories {
jcenter()
}
dependencies {
implementation("com.github.javafaker:javafaker:0.16")
}
Import the project in Eclipse.
Maven
Make sure you have Maven installed by running mvn -version.
Create a directory for your project and navigate into it.
Create a file named pom.xml or build.gradle. It's a project descriptor in Maven:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.your.company</groupId>
<artifactId>app</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>com.github.javafaker</groupId>
<artifactId>javafaker</artifactId>
<version>0.16</version>
</dependency>
</dependencies>
</project>
Import the project in Eclipse.
Is this actually that complicated?
As you see, no, it's not complex at all!
Why can I not just download and add the library to my build path?
You can. This approach just don't scale when you have dozens and hundreds of dependencies (with their own dependencies). Plus, modern software needs not only to be compiled, but tested, packaged, released & distributed. Though you can do most of that from your IDE, but… This appriach just don't scale. Just because people use different IDEs. Because there is no IDE on a build server. Because when you know Gradle or Maven a little bit better, you'll see that it's even faster to accomplish tasks via build tool then via menu items.
Happy hacking!

How to add jar file dependency in pom.xml

I have an application that depends on 2 jar file :
OperatorInterface.jar
Operator.jar
I want to build my project using Maven structure. I've followed the Maven site tutorial to create the structure like so:
mvn -B archetype:generate -DarchetypeGroupId=org.apache.maven.archetypes -DgroupId=source.app -DartifactId=project
I've put my source file FileProcess.java in E:\project\src\main\java\source\app.
FileProcess has dependency in 2 external .jar files but I don't know how to define this dependency in pom.xml.
Here is the content of the pom.xml so far:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>source.app</groupId>
<artifactId>my-app</artifactId>
<packaging>jar</packaging>
<version>1.0-SNAPSHOT</version>
<name>my-app</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
</project>
Can anyone help me?

First thing you need to install your jars in your maven local repository. You can follow the official tutorial here:
https://maven.apache.org/guides/mini/guide-3rd-party-jars-local.html
During the installation you will have to choose your own artifactId, groupId and version. You can choose whatever value you want but remember them because you will need those to include your jars in the pom.
After that you can include them in your pom.xml adding these lines under the tag dependencies for each library to include:
<dependency>
<groupId>your_group_id</groupId>
<artifactId>your_artifact_id</artifactId>
<version>your_version</version>
</dependency>

In the case when the JARs in question are your own code rather than third-party, the best approach is to "mavenize" the projects that build them as well. After you do that, running mvn install on those projects will place them in your Maven local repository where they will be available to other local Maven projects who declare them as dependencies.

Avoid adding them to yourpom.xml file straight. When you add .jars using this process, they will automatically reflect in your pom.xml
Steps are -
1. Right click on your project in the file explorer in your eclipse.
2. Go to build Path option.
3. Select configure build path
4. Chose the Libraries tab in the window that appears.
5. Add your .jar file externally.
6. Click ok and come back to your project interface
Update your maven project by pressing Alt+F5 and restart eclipse. Your problem should be solved.

I would take the following route since this is for corporate use. This is the hard and ultimately portable way that sets you up for future Maven usage as it is intended to be done.
1) make those dependent jars Maven projects (because then you can easily version-manage them too using Maven)
2) use a local repository manager and deploy your own projects to it using Maven release management through either the mvn:release plugin, or use a build server such as Hudson to automate the release process with a simple button press which I can highly recommend setting up.
https://maven.apache.org/repository-management.html
http://maven.apache.org/maven-release/maven-release-plugin/
3) mvn:release the dependency jars to your local repository manager so they will be available for other Maven projects
4) you're actually done, when you have a local repository where your deploy your own snapshot and release artifacts to, then your maven build can find your own maven modules and include them in the application dependencies - if you don't forget to configure the repository in the project's pom of course. And your build server if you have one can find them too.
The easy/lazy route is as suggested to manually install the jars in your local .m2 folder where Maven caches dependencies that it downloads, but it is absolutely not a portable solution that will stand the test of time. It won't work when somebody else needs to work on this project until they too install the jars locally. Or if its only you, you need to redo it every time you checkout the project on another computer / as another user. Also you need to update the jars each and every time you make changes to them, everywhere the project is checked out. You may need to do specific setup steps to get it working in an IDE, should you inevitably choose to start to use one.
However if you are having a time-pressure problem, then I would certainly go ahead and do that as a temporary workaround solution to be able to get going.

Maven not downloading dependencies in Eclipse

I am setting up a project in eclipse . This projects builds successfully through command line(all mvn commands like mvn package, mvn compile, mvn clean install) work perfectly fine. While setting up this project on STS or Eclipse . I see some of the dependencies are not getting downloaded even though they are present in pom.xml. However, searching them in the maven repository and downloading the jar to my local computer and then adding them to build path makes it work on Eclipse.
Is there anything that we need to do to eclipse to make sure it downloads all the dependencies from the repository.
My POM:
<dependency>
<groupId>org.apache.bookkeeper</groupId>
<artifactId>bookkeeper-server-compat410</artifactId>
<version>4.1.0</version>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.apache.bookkeeper</groupId>
<artifactId>bookkeeper-server</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.apache.bookkeeper</groupId>
<artifactId>bookkeeper-server-compat420</artifactId>
<version>4.2.0</version>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.apache.bookkeeper</groupId>
<artifactId>bookkeeper-server</artifactId>
</exclusion>
</exclusions>
</dependency>
Both these artifacts were not downloaded for eclipse and there jars found http://mvnrepository.com/artifact/org.apache.bookkeeper/bookkeeper-server-compat410/4.1.0 and http://mvnrepository.com/artifact/org.apache.bookkeeper/bookkeeper-server-compat420/4.2.0 were not present in the folder for MavenDependencies and were subsequently giving errors in Eclipse.
However manually adding them to the build path created a new folder (Reference Library) and resolved the Eclipse Errors . Why did Eclipse not download and import these dependencies by themselves from the maven repository ?? Is it a bug in Eclipse or some problem from my side . Please help.

I got the same problem and this is how i solved. :
Right click your project, choose Run As -> Maven install.
Observe the output console to see the installation progress. After
the installation is finished, you can continue to the next step.
Right click your Spring MVC project, choose Maven -> Update Project.
Choose your project and click OK. Wait until update process is
finished.
The error still yet, then do Project->Clean and then be sure you have selected our project directory and then do the follow Project->Build.

Solution 1:
Set correct proxy:
<proxy>
<id>optional</id>
<active>false</active>
<protocol>http</protocol>
<username></username>
<password></password>
<host>172.27.171.91</host>
<port>8080</port>
</proxy>
Solution2 :
just delete
lastupdated extension files from folder
and try updating maven.
[Most of the times this solution will work]

Sometimes there is an error downloading a dependency - eg. some files are downloaded but the actual JAR is missing from the local Maven repository.
In this case I had to delete the whole folder of the problematic dependency in the local maven repository. Only then did Maven update work (Right-click on the project and select Project > Maven > Update Project.... )

In my case, I had unchecked Build automatically. Checking it again started downloading the jars.

I have come across the same issue recently.
First of all you have to configure proxy settings in settings.xml in your maven repository.
If you are using eclipse/STS then please do verify following.
Window -> Preferences -> Maven -> User Settings -> update user settings by pointing your settings.xml
Now it's set to update the maven project. It worked for me.

I was facing similar sort of issue. I tried deleting folders inside .m2 and again building maven project.
I could download all dependency except one dependency which we have created by ourselves and published on Nexus.
Then I changed by java pointing from JRE to JDK which solved my problem

The following worked for me.
Just right-click on Project -> Maven -> Update Project... such as it is shown here.

I had faced a similar issue and following the below steps helped me fix it.
Delete the last modified jar from respective folders.
Select the project
Right Click -> Maven
Update project..
It will download all the missing Jars.

Try to move your dependencies from "type" tag to "scope" tag like below
or
<dependency>
<groupId>net.xyz.xyz</groupId>
<artifactId>xyz-xyz</artifactId>
<version>x.y.z</version>
<type>pom</type>
</dependency>
or
<dependency>
<groupId>net.xyz.xyz</groupId>
<artifactId>xyz-xyz</artifactId>
<version>x.y.z</version>
<scope>test</scope>
</dependency>
then further Maven > Update Project

For me I changed the packaging from pom to jar, and then the dependency got downloaded.
so I changed from <packaging>pom</packaging> to <packaging>jar</packaging>

Make sure you're defining the dependency as close as possible to the leaf of the project tree where it is needed. Otherwise, Maven might ignore it.
For example, if you have a parent project that references projects A and B and the dependency is with respect to project A, then defining the dependency in the parent's pom.xml might get ignored by Maven. So, define it in project A's pom.xml.
Parent Project's pom.xml
Sub-project A's pom.xml <<< define the dependency where it is needed
Sub-project B's pom.xml

I hope this helps someone as it took me 2 days to realize. I re-imported the project multiple times and followed every possible step I've seen online and in the end I had added a small piece of xml code within the pom.xml. Even though it wasn't erroring or even showing a warning it was preventing maven from reading the lifecycle-mappings.
Click into your pom.xml and go to the dependencies tab on the bottom left, if you see an error there it's likely your pom.xml is corrupted in some way and maven will never attempt to download the dependencies even though you won't get any real error. I had looked back at a previous PR and noticed where/what I added and removed it and was able to get maven to work.

How to add dependency to jfugue using eclipse?

I'm working on a project on Eclipse IDE that requires jfugue. How do I add this dependency to my project, using Maven?
I tried to:
Right click to the project name->Maven->Add Dependency;
I added a dependency from pom.xml form:
<dependency>
<groupId>org</groupId>
<artifactId>jfugue</artifactId>
<version>4.1.0</version>
<type>java-source</type>
</dependency>
I added the repository:
<repository>
<id>jfugue-repo</id>
<url>http://jfugue.googlecode.com/svn/trunk/jfugue/</url>
</repository>
It search files with a broken link but I can't see it because it not appear for more than one second in the Progress View.
How can I fix this? Thanks for your help.
UPDATE 1
jfugue pom.xml is this.
Mine pom.xml is this.

It seems that the pom.xml doesn't have remote repositories. Use the following link to figure out how to install jar into the local repository. You have also remove <repository tag from your project's pom.xml.

Successful build in Maven still showing errors in Eclipse

I'm having something quite peculiar here, my build is successful in maven when I type "mvn clean install" however once imported into Eclipse it's showing errors.
See for yourself:
I guess exluding quartz from the `pom.xml solved the problem but I'd like to know why.
PS: Here is the pom.xml in case you want to see it:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.nantes.mpclient</groupId>
<artifactId>MyClient</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<name>MyClient</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.nantes.mp</groupId>
<artifactId>MyEjb</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.jboss.jbossas</groupId>
<artifactId>jboss-as-client</artifactId>
<version>5.1.0.GA</version>
<type>pom</type>
</dependency>
</dependencies>
</project>
###EDIT
As you can see quartz is here:

Updating maven project after importing it has fixed this issue for me:
Right click on the project --> Maven --> Update project.

Sometimes I get these types of issues as well.
Generally, what worked best for me with Eclipse & Maven:
Use the latest m2e Eclipse plugin
Use Maven 3
Make sure m2e uses the same Maven version as the one you're using on the command line (not the internal one)
Import projects as Maven projects to generate the Eclipse project files

The other upvoted answers did not work for me using these versions:
Eclipse Neon
Maven 3
m2e 1.7
This is what I had to do:
Delete the Eclipse project from Eclipse interface (do not delete project contents on disk)
Go to the project's root directory in a file explorer or terminal
Delete these files: .classpath, .project, and .settings directory
Back to Eclipse, File -> Import... -> Maven -> Existing Maven projects

If you don't see any error in Eclipse project but it keeps showing the red icon on your project name. Try mvn eclipse:eclipse.
Then select all projects in Eclipse, Right click > Maven > Update projects
Hope it helps.

You should try mvn eclipse:eclipse
And then make sure the M2_REPO variable is point to your local repository.

sometimes maven update nor all above works.
so check which import statement gives you error, then go particular lib file which is usually in c:user/ur-PC-NAME/.m2 get into package delete that .jar file.
then in eclipse, right click on project > maven > update maven.

Sometimes the m2e "maintained" eclipse project is out-of-sync with the actual project in POM (There are lots of reason for that). Assume you have using m2e 0.8 or later, right click on the project, under Maven, there are two entries that are usually useful. They are Update Dependencies and Update Project Configuration
Have a try on them, wait a while after u clicked that for eclipse to update the project and build. Normally it solves similar problems.

That often happens when the m2eclipse hasn't updated the build path to correspond to what a modified POM file says. There's an entry in the Maven context menu to update the Configuration.

In my case,
I just deleted project from Eclipse (not ticked checkbox to delete
from project location).
Opened project as "Existing Maven Project" again.
and it solved my issue.

I found that my project was using a project specific Java Compiler setting set to Java 1.5. Furthermore, the project facets were still referencing Java 1.5 when Maven, m2e, Eclipse general Java Compiler settings were all set to Java 1.8.

In my case there were also problems with Java build path like the following:
"Build path specifies execution environment J2SE-1.5. There are no JREs installed in the workspace that are strictly compatible with this environment." Fixing this resolved compilation errors.

You've a library (quartz-1.5.2.jar) that's reference to your m2 local repository which doesn't exist if you just remove the quartz from your build path and update your dependencies internally(in eclipse) that would solve the problem

Try to use different/older version of JRE. In my case switching back to JRE7 from JRE8 eliminated the problem.

Delete and Re-Import the project in eclipse (without deleting files of course). Unlike other answers I have not looked into why this happens but it works. poof - compilations errors be-gone

It may help: After upgrading eclipse or changing it or something like, old eclipse specific files (.classpath, .project, and .settings) may not be compatible to the new version of eclipse. So you may have to re generate this eclipse specific files using Maven. So try this in your eclipse project root
mvn eclipse:eclipse

In my case, eclipse starts to show all errors after I changed some versions of dependencies in pom.xml, however the command line mvn clean install build successfully
I deleted folders of the dependencies I changed manually from the .m2 repositories (in my case everything under org.apache.beam), because I also has corrupted dependency issues.
mvn clean build the project, this downloaded the dependencies again
right click project: maven -> update project
delete the project from eclipse (but not from disk) and reimport (this actually left me with 1 error still, then i delete and reimported again)

Go to Eclipse> Project (Menu) > Clean... > Select project to clean
This also removes invalid errors from Eclipse.

For me Right click on the project --> Maven --> Update project with the "Force Update of Snapshots/Releases" checkmarked worked.

Some times, eclipse's validation causing these errors.
You can disable them by going to Menu>window>preferences>validation and uncheck suspend all validators or disable them one by one for builds.
E.G, every time You build the project eclipse does not validate your files and does not show up those errors.

This worked for me
Delete the Eclipse project from Eclipse interface (do not delete
project contents on disk)
Go to the project's root directory in a
file explorer or terminal
Delete these files: .classpath, .project,
and .settings directory
Back to Eclipse, File -> Import... -> Maven
-> Existing Maven projects

Got the same problem, I deleted the project from my workspace (not on disk), opened the project folder and deleted the files .project, .classpath and the folder named .settings.
Now goto eclipse again, import the same project again and viola my error is gone!