How to make one module depend on another module ar

问题:

I have maven multiple-module project.

 A: parent.
    B: child1.
    C: child2.

B will be packaged to get jar file and then c will use this jar file to compile the code.

In B, if I run mvn package, it will create b.jar (stays in B/target/jars not in B/target -for another purpose).

In C, I need to use that b.jar to compile the code.

Now, from A, when I run: mvn package. First, I am successful to create b.jar file for B.

But when it come to C's compilation phase, it looks like C doesn't recognize b.jar in the classpath (the compilation gets errors because C's code can not import the class file from B).

My question is: How can I solve this problem?

---------- Below are the pom files

A: pom.xml
  <groupId>AAA</groupId>
  <artifactId>A</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>pom</packaging>

   <modules>
   <module>C</module>
   <module>B</module>
   </modules>

B: pom.xml
        <groupId>AAA</groupId>
 <artifactId>B</artifactId>
 <packaging>jar</packaging>
 <version>0.0.1-SNAPSHOT</version>
 <parent>
  <artifactId>A</artifactId>
  <groupId>AAA</groupId>
  <version>0.0.1-SNAPSHOT</version>
 </parent>

C: pom.xml
       <parent>
  <artifactId>A</artifactId>
  <groupId>AAA</groupId>
  <version>0.0.1-SNAPSHOT</version>
 </parent>

 <groupId>AAA</groupId>
 <artifactId>C</artifactId>
 <packaging>war</packaging>
 <version>0.0.1-SNAPSHOT</version>

 <dependencies>

  <dependency>
   <groupId>AAA</groupId>
   <artifactId>B</artifactId>
   <version>0.0.1-SNAPSHOT</version>
  </dependency>
....

回答1:

Looks like it should work to me. But you might try mvn install instead of mvn package.

回答2:

My question is how I can solve this problem?

Dependency resolution is done through the local repository so the canonical way to "solve" the problem is to run install from A so that modules will get installed in the local repository.

Now, regarding the following comment

But if I go with install then c war file will also be installed. That one is not accepted in my current project".

Sure, I'm not on your project, I don't know all constraints and rules. But if you decide to use Maven, this is a totally ridiculous policy (seriously, WTF?) and using a system scoped dependency is certainly not a good solution (more troubles later guaranteed). If this policy is real, better not use Maven in that case.

回答3:

Try ${project.version}

e.g.

<dependency>
   <groupId>AAA</groupId>
   <artifactId>B</artifactId>
   <version>${project.version}</version>
  </dependency>

回答4:

i have a solution: using the dependency with the scope=system

in C pom.xml

           <dependency>
            <groupId>AAA</groupId>
            <artifactId>B</artifactId>
            <version>0.0.1-SNAPSHOT</version>
            <scope>system</scope>
            <systemPath>${basedir}\..\B\target\jars\b.jar</systemPath>
        </dependency>

and in A pom.xml, put module B on the top like this

<modules>
       <module>B</module>       
       <module>C</module>
 </modules>

回答5:

Doing mvn install only places the artifact into the local .m2 repository of the machine you're running the command on. How can that not be acceptable? I agree with Pascal. If you building A, there should be no reason that a the war is placed there.

On the other hand, if you're using Maven 2.2.x, take a look at the maven reactor plugin? This should help the crazy unacceptable cannot install C.war into your local .m2 repository policy for the current project.