Invalid packaging for parent pom.xml, must be “pom” but is “ear”

问题

Could anybody suggest me an solution with the following exception. I am going to create a multi-module project.

Parent Project name is LOGICBACKEND child project name is DBAccess

I need to have ear file of LOGICBACKEND which should contain DBAccess prjoects jar file.

I am getting following exception when i run mav clean install -P Developer.

[ERROR]The project com.project1.Database:DBAccess:1.0-SNAPSHOT (C:\Project1\DBAccess\pom.xml) has 1 error
[ERROR]Invalid packaging for parent POM com.project1.logic:LOGIC:1.0-SNAPSHOT (C:\Project1\pom.xml), must be "pom" but is "ear" @ com.project1.logic:LOGIC:1.0-SNAPSHOT, C:\Project1\pom.xml, line 6, column 13

This is how part of my parent pom.xml looks

<modelVersion>4.0.0</modelVersion>
<groupId>com.project1.logic</groupId>
<artifactId>LOGICBACKEND</artifactId>
<packaging>ear</packaging>
<version>1.0-SNAPSHOT</version> 

This is how child pom.xml looks

<groupId>com.project1.logic</groupId>
<artifactId>DBAccess</artifactId>
<packaging>ejb</packaging>
<name>DBAccess</name>
<version>1.0-SNAPSHOT</version>

<parent>
    <groupId>com.project1.logic</groupId>
    <artifactId>DBAccess</artifactId>
    <version>1.0-SNAPSHOT</version>
    <relativePath>../pom.xml</relativePath>
</parent>

Could anybody help me here to understand what is going wrong here.

Thanks in advance for any help

回答1:

This simple setup is a good start.

.
├── pom.xml
├── services
|   ├── pom.xml
|   └── src
|       └── main
|           └── java
|               └── com
|                   └── stackoverflow
|                       └── MyEjbService.java
└── application
    └── pom.xml

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.stackoverflow.Q13330930</groupId>
    <artifactId>parent</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>pom</packaging>

    <name>${project.artifactId}-${project.version}</name>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <modules>
        <module>services</module>
        <module>application</module>
    </modules>

    <dependencies>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.stackoverflow.Q13330930</groupId>
                <artifactId>services</artifactId>
                <version>${project.version}</version>
                <type>ejb</type>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-ejb-plugin</artifactId>
                <version>2.3</version>
                <configuration>
                    <ejbVersion>3.1</ejbVersion>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

services/pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <parent>
        <groupId>com.stackoverflow.Q13330930</groupId>
        <artifactId>parent</artifactId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <groupId>com.stackoverflow.Q13330930</groupId>
    <artifactId>services</artifactId>
    <packaging>ejb</packaging>

    <name>${project.artifactId}-${project.version}</name>

</project>

application/pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <parent>
        <groupId>com.stackoverflow.Q13330930</groupId>
        <artifactId>parent</artifactId>
        <version>1.0-SNAPSHOT</version>
    </parent>

    <groupId>com.stackoverflow.Q13330930</groupId>
    <artifactId>application</artifactId>
    <packaging>ear</packaging>

    <name>${project.artifactId}-${project.version}</name>

    <dependencies>
        <dependency>
            <groupId>com.stackoverflow.Q13330930</groupId>
            <artifactId>services</artifactId>
            <type>ejb</type>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-ear-plugin</artifactId>
                <version>2.7</version>
                <configuration>
                    <defaultLibBundleDir>lib</defaultLibBundleDir>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

回答2:

You are trying to give the parent pom two functions - that is serving as a parent pom (packaging pom) and being the wrapper ear (packaging ear) - at the same time. To solve your issue you should create another maven module under your parent pom that has packaging ear and uses the maven-ear-plugin to define the output.

来源：https://stackoverflow.com/questions/13330930/invalid-packaging-for-parent-pom-xml-must-be-pom-but-is-ear