I have got two Maven projects. One of them has to be dependent on the other. I use IntelliJ and I have tried to right click on project1 > Open Module Settings, and in the dependencies tab I clicked on the + symbol to add a directory or jar dependency. So far so good, when I try to import packages from the dependency it autocompletes it for me, however the compilation throws errors, saying that there are no such packages. What am I doing wrong ?
There is no notion of project in Maven.
You have a Maven project B. You chose its groupId (com.mycompany, for example), its artifactId (B, for example), and its version (1.0-SNAPSHOT, for example). You run mvn install on this project. This generates a B-1.0-SNAPSHOT.jar file and stores it in your local Maven repository, with its pom.
Now you want to use B-1.0-SNAPSHOT.jar in another Maven project A. For A, B is a library, just like any other library you use (log4J, Spring, Hibernate, Guava, whatever). So you add a dependency to it in the pom of A, just like you do for any other library:
<dependencies>
<dependency>
<groupId>com.mycompany</groupId>
<artifactId>B</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
<!-- other dependencies: log4J, Spring, Hibernate, Guava, whatever -->
</dependencies>
Read the awful documentation for more details.
Related
Intellij version : Community 2019.2.3
Maven : 3.6.2
Spring : 2.2.0
I am trying to create a very simple Spring maven project with two sub-modules (one independent and another one dependent on independent one).
Root module - testmultimodule
Independent module - independent
Dependent module - dependent
testmultimodule pom.xml has all Spring related declaration and module definition
<modules>
<module>independent</module>
<module>dependant</module>
</modules>
Independent poom.xml is simplest and . only has parent maven declaration
<parent>
<artifactId>testmultimodule</artifactId>
<groupId>in.org.app</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
dependent module pom.xml has the dependency declaration as below to independent module
<dependencies>
<dependency>
<groupId>in.org.app</groupId>
<artifactId>independent</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
</dependencies>
I have created a Test class under dependent module and using a User object from independent module. Initially, without the above dependency declaration, asa usual there was compilcation error.
As soon as I add the dependency and builld the project within Intellij IDE with the option "Build Prooject" option from "Build" menu, it successfully builds.
However, if I try to use Maven install option within Intellij right side window option. It always fails stating Error:(3,33) java: package in.org.app.independent.bo does not exist .
I am providing the GitHub URL for the test project , if you want to take a look and test by yourself.
GIT URL:
https://github.com/DhruboB/testmultimodule
I have tried all sort of tweaking found in internet so far e.g.
clearing Intellij Cache & restarting, mvn -U clean install, mvn scope verification, proxy etc.
Any further idea to resolve this? I need to solve this in the Community version of Intellij.
Your parent project includes the definition for the spring-boot-maven-plugin. This leads to each project defining this as a parent to be repacked to an executable JAR by this plugin. This repackaged JAR isn't useable as a dependency in another project.
Either you need to change the configuration of the spring-boot-maven-plugin for the project you want to use as a dependency. This is explained here in the Spring Boot Reference Guide. You now basically have 2 jars from this project, one plain and one executable.
If you don't need that project to be an executable JAR file then just move the spring-boot-maven-plugin to the project that needs to be. All other projects will no be basic JAR files again.
See also How to add a dependency to a Spring Boot Jar in another project?
I'm having trouble correctly importing a library into a project that I'm running. I have added the library as a dependency in the .pom, refreshed the pom, run mvn clean install, and I have set auto-import up so that the project gets updated correctly, but the project does not get added as an External Library, and I can't use it in my project. I get no errors. What am I doing wrong?
Here is the relevant part of my pom
..properties
<crowd.version>2.5.0</crowd.version>
.. end properties
<dependencyManagement>
<dependencies>
<dependency>
<groupId>com.atlassian.crowd</groupId>
<artifactId>crowd-integration-springsecurity</artifactId>
<version>${crowd.version}</version>
<scope>runtime</scope>
</dependency>
</dependencies>
</dependencyManagement>
Here is the question I was following to debug my error:
Import Maven dependencies in IntelliJ IDEA
I think you missed the point of dependency management; read more in official docs. This is a feature that you can centralize common dependency information that is then shared been different projects. All by itself, this definioition will not import the dependency.
What you probably want is just a plain dependency: drop the dependencyManagement tags, and move you dependency into the correct block in the pom.
I have a few dependencies in Project Structure/Libraries in IntelliJ 14. How can I add them to my maven pom.xml? There is one single tutorial on IntelliJ's website that does not work for me. I don't want to manage them manually.
The proper way to do this would be to install the dependency artifacts (most likely jars) into your local maven repo, like this.
How to install artifacts to your local maven repo
And then add the dependencies into your pom.xml
<dependencies>
<dependency>
<groupId>com.something</groupId>
<artifactId>artifact</artifactId>
<version>1.2.3</version>
</dependency>
</dependencies>
Yes, this does require going through each artifact manually, one at a time, but it's a one time setup process.
That is the "proper" way. After that, you can do away with library dependencies in your project structure (they will be picked up correctly via maven).
There is the alternative possibility to "hack" in your project libraries path as a sort of "embedded" maven repo in your project, but that's a little bit hacky and I wouldn't advise that.
Project A references Project B. Project B has included a local dependency. This local dependency unfortunately has a dependency to net.java.dev.designgridlayout in version 1.5.
We want to use net.java.dev.designgridlayout in version 1.11 in Project A but we are not able to "overwrite" the dependency. Eclipse always uses the dependency from Project B.
We already tried to exclude the 1.5 version from the local dependency, but it doesn't work.
The strange thing is, that Eclipse successfully resolves a class that has been added with version 1.11. For an already existing class, however, eclipse resolves it from the transitive dependency from de.someCompany.
Project B:
<dependencies>
<dependency>
<groupId>de.someCompany</groupId>
<artifactId>fs-client</artifactId>
<version>5.1.209</version>
<exclusions>
<exclusion>
<groupId>net.java.dev.designgridlayout</groupId>
<artifactId>designgridlayout</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>net.java.dev.designgridlayout</groupId>
<artifactId>designgridlayout</artifactId>
<version>1.11</version>
</dependency>
</dependencies>
Project A:
<dependencies>
<dependency>
<groupId>Project-B</groupId>
<artifactId>Project-B</artifactId>
<version>1503.01</version>
</dependency>
</dependencies>
I also tried to include the 1.11 dependency in Project A.
We even tried to install the DesignGridLayout V. 1.11 in the local dependency and to change the groupID and artifactId to something different, but it cannot even be found by Eclipse for some reason. If it would be possible to include the DesignGridLayout with another groupId and artifactId, I think it would work.
mvn install:install-file -Dfile=lib\designgridlayout.jar -DgroupId=com.company.designgridlayout -DartifactId=design-grid-layout -Dversion=1.11 -DgeneratePom=true -Dpackaging=jar -DlocalRepositoryPath="%USERPROFILE%\.m2\repository"
Not sure - but:
Your project A has a dependency to itself? Shouldn't it use project-b?
Its not a good idea to change group or artifact id's as maven can no longer detect its the same artifact. If you do a custom version the version number should be enough.
If you add the dependency in your own pom then you don't need to exclude the artifact, since the groupId and artifactId are the same. The version in your own pom will win in project-b. If project a defines that dependency again itself that version will win.
I would do a mvn dependency:tree on project-a pom to see where the dependencies come from.
For eclipse: it indexes the local repository. In the maven settings there is a re-index button. So if you manually copy jars in there that may help eclipse to find the artifact. But that workaround would need to be done on every machine. I would not count that as solution. In the maven world artifact-resolution is an infrastructure issue and should not be handled per project. The way this is done should be transparent through the settings.xml
I'm new to Maven, I try to use Maven with Spring, Hibernate in my project. After go though the Spring and Hibernate reference, I found that "there is no need to explicitly specify the dependent liberaries in POM.xml file for such Apache commons liberaries".
My questions is that : If my other parts of project refer to Apache commons liberary, such as commons-io, SHOULD I explicit specify this dependency in POM.xml file?
You should define those dependencies in Maven which your project is using. For example, even though some library depends on commons-io but if your code needs this then you should directly define commons-io in your pom.xml
You should not worry about the dependencies of the libraries you have defined in your pom.xml. Maven will do that for you.
Maven is used to avoid the issue of having to run down JAR files that are dependent on other JAR files. Of course you do not HAVE to use maven to do this, but you should. Maven will automatically download the dependent JAR files of the JAR file you require. THe hibernate-entity manager JAR file, for example, has over 100 dependencies and maven does the work for you.
Anyway,even if you do add the commons-io file to the build path/classpath of the maven project,and then update the project configuration, maven will kick it out.
You can provide a lib name on a site like mvnrepository.com to see what it depends on (e.g. take a look at a section called "This artifact depends on ..." in case of spring-webmvc library). Those dependencies (which your artifact depends on) are called transitive dependencies. You don't have to specify these in your pom.xml as maven will resolve them for you.
For the sake of readability you should only state those dependencies in your module that you rely on directly. You want JUnit to test your software, only declare JUnit; you need hibernate to use ORM, declare hibernate, and so on. Leave the rest to Maven.
And most of the time you should state what you intend to use in the very module you want to use it in. So if you want to use a dependency in more than one module, consider moving it into a dependencyManagement block in a parent pom and referencing it from there in the module you want it in.
parent pom.xml
<dependencyManagement>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.10</version>
<scope>test</scope>
</dependency>
</dependencies>
</dependencyManagement>
child pom.xml
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
</dependency>
</dependencies>
This guarantees you version-stability and still allows you to find out what a module uses by only looking in it's pom (and not all over the place).