Generating WAR files from a multiproject Maven configuration

Question

I have a Maven project, with 4 components Web, Persistence, Common and Other.

The relevant stuff off my POM files:

Parent POM:

<groupId>com.test</groupId>
<artifactId>test</artifactId>
<packaging>pom</packaging>
<version>0.0.1-SNAPSHOT</version>
<modules>
    <module>components/TestWeb</module>
    <module>components/TestOther</module>
    <module>components/TestPersistence</module>
    <module>components/TestCommon</module>
</modules>


<build>
    <defaultGoal>package</defaultGoal>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>2.0.2</version>
            <configuration>
                <source>1.5</source>
                <target>1.5</target>
            </configuration>
        </plugin>

        <plugin>
            <artifactId>maven-war-plugin</artifactId>
            <version>2.1</version>
            <configuration>
                <dependentWarExcludes>
                    **/hibernate.cfg.xml,**/sql-map-config.xml,**/web.xml,WEB-INF/classes/META-INF/**
                </dependentWarExcludes>
            </configuration>
        </plugin>
     </plugins>
 </build>

common pom:

<modelVersion>4.0.0</modelVersion>
<artifactId>test-common</artifactId>
<packaging>jar</packaging>
<version>0.0.1-SNAPSHOT</version>

<parent>
    <groupId>com.test</groupId>
    <artifactId>test</artifactId>
    <relativePath>../../pom.xml</relativePath>
    <version>0.0.1-SNAPSHOT</version>
</parent>

persistence pom:

<modelVersion>4.0.0</modelVersion>
<groupId>com.test</groupId>
<artifactId>test-persistence</artifactId>
<packaging>jar</packaging>
<version>0.0.1-SNAPSHOT</version>

<parent>
    <groupId>com.test</groupId>
    <artifactId>test</artifactId>
    <relativePath>../../pom.xml</relativePath>
    <version>0.0.1-SNAPSHOT</version>
</parent>


<dependencies>
  <dependency>
    <groupId>com.test</groupId>
    <artifactId>test-common</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </dependency>
</dependencies>

web pom:

<modelVersion>4.0.0</modelVersion>
<groupId>com.test</groupId>
<artifactId>test-web</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>TestWeb</name>

<parent>
    <groupId>com.test</groupId>
    <artifactId>test</artifactId>
    <relativePath>../../pom.xml</relativePath>
    <version>0.0.1-SNAPSHOT</version>
</parent>

  <dependency>
    <groupId>com.test</groupId>
    <artifactId>test-common</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </dependency>


  <dependency>
    <groupId>com.test</groupId>
    <artifactId>test-persistence</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </dependency>


  <dependency>
    <groupId>com.test</groupId>
    <artifactId>test-other</artifactId>
    <version>0.0.1-SNAPSHOT</version>
  </dependency>

Maybe I broke something in the copy&paste, but the XML is valid.

• when I run mvn package, the project WAR file isn't created, but all components packages are created and well formed.
• if, then, I run mvn war:war, the WAR file is generated empty.

How can fix this?

Answer 1

Having plugins in the root project does not work. You can configure the plugins here, like this

<build>
    <pluginManagement>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.0.2</version>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                    <encoding>${project.build.sourceEncoding}</encoding>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <version>2.2</version>
                <configuration>
                    <encoding>${project.build.sourceEncoding}</encoding>
                </configuration>
            </plugin>
        </plugins>
    </pluginManagement>
</build>

but they still have to be referenced in the subprojects to be active (except for plugins that are part of the default process, like maven-compiler-plugin and maven-resource-plugin).

So either you move your war-plugin configuration to pluginManagement in the root project and include

<build>
    <plugin>
        <artifactId>maven-war-plugin</artifactId>
        <version>2.1</version>
        <execution>
            <goals>...</goals>
        </execution>
    </plugin>
</build>

in your war project or you move the entire configuration into the war.

Additional note: Make sure the order of the modules in the root pom is aligned to the dependency relations between the projects (In your case just reverse the order).