将JAR Maven项目纳入WAR Maven项目

Question

I have two Maven projects: Project1 that packages to JAR, and Project2 that packages to WAR.

<!-- Project1's POM -->
<groupId>foobar</groupId>
<artifactId>project1</artifactId>
<version>1.0</version>
<packaging>jar</packaging>

<!-- Project2's POM -->
<groupId>foobar</groupId>
<artifactId>project2</artifactId>
<version>1.0</version>
<packaging>war</packaging>

I want to include Project1 into Project2, so in Project2's POM, I added:

<dependency>
    <groupId>foobar</groupId>
    <artifactId>project1</artifactId>
    <version>1.0</version>
</dependency>

But Project2 is not able to resolve this dependency.

In Project2's properties, Java Build Path > Libraries, I can see Project2 looking for "project1-1.0.jar" in my "~/.m2" folder. Is this normal?

Did anyone meet this problem too and finally find a solution? I can't make it work, even when looking to answers of related questions in SO.

---

• Eclipse Kepler
• Maven 3.0.4
• Maven Integration for Eclipse WTP (Juno) 1.0.1

Answer 1

Unless you run maven install on your project1 . It would not be packaged as a jar file into your .m2 repository, and hence it wouldnt be resolved in the project2 's pom file.

This is similar to using a third party jar file. But not having it in the .m2 repository. Even in that case, you would face the same problem.

For your project 2, project 1 is treated as an independent third party jar file. It needs to be in your .m2 repository so that it resolves it.

Answer 2

To ensure that Eclipse WTP understand that your projects depend on each other, you need to define a multi-module parent project for both. Otherwise, you need to "mvn install" project1 every time that you update it, and you will see the dependency go through ~/.m2 as you observed.

There are many resources on the web about multi-module projects - the biggest choice you need to make is whether you want a flat layout (all project directories, including that of the parent module project, in the same base directory) or a hierarchical layout (the parent module project directory contains the sub module project directories).