Maven - How to unit test a project dependent on another project?

Question

I know this question has been asked numerous times but the methods I've read just doesn't work for me. I tried this but it still won't work.

I have a subproject(A) that depends on another subproject(B).

Both subprojects are contained in a parent directory with a parent pom.xml (declares A and B as modules) within their respective subdirectories.

Compiling and installing the project works fine with the maven-assembly-plugin but when I try to test A, it doesn't recognize the classes from B. I have tried installing it first and then testing but it still won't find the classes. What am I missing?

Error:

 [ERROR] Failed to execute goal
 org.apache.maven.plugins:maven-compiler-plugin:3.1:testCompile
 (default-testCompile) on project (A)

[ERROR] TestService.java:[8,17] cannot find symbol 

[ERROR]   symbol:   class **Model** (the class I'm referencing in B)

[ERROR]   location: class **TestService** 
(test in A that tests the class in ../service/src/main/java/Service.java)

Edit:
/project
--/service (this depends on model;this is also what I want to test)
---/src
----/main
-----/java
------/Service.java
----/test
-----/java
------/TestService.java

--/model (independent)
---/src
----/main
-----/java
------/Model.java

--/entry (this depends on service; entry point of the whole project)
--pom.xml (parent pom)

Each of the three projects have their own pom.xml inside.

/model/pom.xml contains no dependencies and no plugins

here's parent: parent/pom.xml

  ...
  <modules>
    <module>entry</module>
    <module>service</module>
    <module>model</module>
  </modules>

here's entry:

 /service/pom.xml
        ...
    <parent>
        <groupId>com.some.project</groupId>
        <artifactId>project</artifactId>
        <version>xx</version>
    </parent>
    <artifactId>entry</artifactId>
    <packaging>jar</packaging>
    <version>xx</version>
    <name>entry</name>
    <build>
     ...
     <!--assembly plugin is declared here-->
    </build>
    <dependencies>
      <dependency>
      <groupId>com.some.project</groupId>
      <artifactId>service</artifactId>
      <version>xx</version>
      </dependency>
    </dependencies>

here's service:

/service/pom.xml
    ...
<parent>
    <groupId>com.some.project</groupId>
    <artifactId>project</artifactId>
    <version>xx</version>
</parent>
<artifactId>service</artifactId>
<packaging>jar</packaging>
<version>xx</version>
<name>service</name>
<dependencies>
  <dependency>
  <groupId>com.some.project</groupId>
  <artifactId>model</artifactId>
  <version>xx</version>
  </dependency>

<dependency>
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>4.12</version>
  <scope>test</scope>
</dependency>
</dependencies>

Show the code or error message please. – Dean Xu Jul 25 '18 at 02:43 — Dean Xu, Jul 25 '18 at 02:43

score 0 · Accepted Answer · answered Jul 25 '18 at 02:57

0

Maven assembly plugin is used usually when you want to package the already compiled sources, so its kind of not related here.

If you have two projects, A and B and B has to depend on A, you have to define in B's pom.xml a dependency (trivial stuff):

<dependency>
  <groupId>YOUR_GROUP_ID</groupId>
  <artifactId>A</artifactId>
  <version>YOUR_VERSION</version>
</dependency>

This will instruct maven to setup classpath during the build.

Now, Depending on artifact type of A and B maven can decide on some steps after the compilation, for example, if B is a WAR, A will be included in WEB-INF/lib folder of B because of such a dependency.

But in general, if A & B are jars, maven won't use this information only for the compilation/tests and not for packaging.

Now, maven has different classpaths for different phases: in particuler, one for compilation, and one for unit tests.

So if you want to specify that the dependency is required only for tests but should not be considered as a "compile" dependency, then define the scope:

<dependency>
  <groupId>YOUR_GROUP_ID</groupId>
  <artifactId>A</artifactId>
  <version>YOUR_VERSION</version>
  <scope>test</scope>
</dependency>

If you don't specify any scope, maven will conclude that the dependency is required both for compilation and for tests and maybe even for packaging as I've explained earlier.

answered Jul 25 '18 at 02:57

Mark Bramnik

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I have added it as a dependency but the Test Classes for B still won't find the classes in A. I have tried using the "compile" scope and "test" scope. – ReconditusNeumen Jul 25 '18 at 04:02
Any chance the the class from A you refer in B resides in "src/test/java" and not in "src/main/java"? Can you use classes from A's src/main/java ? – Mark Bramnik Jul 25 '18 at 04:23
The class from A that I'm referring to in B is in "src/main/java". It's a model class that B needs (B is a service class) and so if I want to test B, I need to instantiate the class in A. (Again for clarity in this case, B depends on A; B is a service, A is a model) – ReconditusNeumen Jul 25 '18 at 04:47
In this case, it's a use case that is totally supported by maven, so the problem must by purely technical with some wrong definitions in pom.xmls. I'm affraid, without actual pom-s and a sample file of service and model it won't be easy to help you out here – Mark Bramnik Jul 25 '18 at 04:50
Did you run Maven from the parent project or in project A? – jensp Jul 25 '18 at 05:17
@MarkBramnik I've now included the pom.xml along with some other sub-projects that might be of concern. – ReconditusNeumen Jul 25 '18 at 05:21
@jensp I tried it with both and it still won't test. It can package and install if I remove the tests though. – ReconditusNeumen Jul 25 '18 at 05:22

Maven - How to unit test a project dependent on another project?

1 Answers1