Summary of common configurations of MAVEN POM files

Reprinted from http://www.cnblogs.com/phoebus0501/archive/2011/01/26/1945374.html

 

What is POM

Project Object Model, the project object model. The pom.xml file saved in xml format. The function is similar to the build.xml file of ant, and the function is more powerful. This file is used to manage: source code, configuration files, developer information and roles, issue tracking system, organization information, project authorization, project url, project dependencies, etc.

 

A complete pom.xml file, placed in the root directory of the project.

<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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <!– The Basics –>
  <groupId>…</groupId>
  <artifactId>…</artifactId>
  <version>…</version>
  <packaging>…</packaging>
  <dependencies>…</dependencies>
  <parent>…</parent>
  <dependencyManagement>…</dependencyManagement>
  <modules>…</modules>
  <properties>…</properties>
  <!– Build Settings –>
  <build>…</build>
  <reporting>…</reporting>
  <!– More Project Information –>
  <name>…</name>
  <description>…</description>
  <url>…</url>
  <inceptionYear>…</inceptionYear>
  <licenses>…</licenses>
  <organization>…</organization>
  <developers>…</developers>
  <contributors>…</contributors>
  <!– Environment Settings –>
  <issueManagement>…</issueManagement>
  <ciManagement>…</ciManagement>
  <mailingLists>…</mailingLists>
  <scm>…</scm>
  <prerequisites>…</prerequisites>
  <repositories>…</repositories>
  <pluginRepositories>…</pluginRepositories>
  <distributionManagement>…</distributionManagement>
  <profiles>…</profiles>
</project>

基本设置

maven的协作相关属性

<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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.codehaus.mojo</groupId>
  <artifactId>my-project</artifactId>
  <version>1.0</version>
  <packaging>war</packaging>
</project>

1. groupId : 组织标识，例如：org.codehaus.mojo，在M2_REPO目录下，将是: org/codehaus/mojo目录。
2. artifactId : 项目名称，例如：my-project，在M2_REPO目录下，将是：org/codehaus/mojo/my-project目录。
3. version : 版本号，例如：1.0，在M2_REPO目录下，将是：org/codehaus/mojo/my-project/1.0目录。
4. packaging : 打包的格式，可以为：pom , jar , maven-plugin , ejb , war , ear , rar , par

POM之间的关系

主要用于POM文件的复用。

依赖关系：依赖关系列表（dependency list）是POM的重要部分。

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.0</version>
      <scope>test</scope>
    </dependency>
    …
  </dependencies>

1. groupId , artifactId , version :
2. scope : compile(default),provided,runtime,test,system
3. exclusions

继承关系：继承其他pom.xml配置的机制。

比如父pom.xml：

<project>
  [...]
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.4</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
  [...]
</project>

在子pom.xml文件继承它的依赖（还可以继承其他的：developers and contributors、plugin lists、reports lists、plugin executions with matching ids、plugin configuration）：

[...]
<parent>
<groupId>com.devzuz.mvnbook.proficio</groupId>
  <artifactId>proficio</artifactId>
  <version>1.0-SNAPSHOT</version>
</parent>
[...]

在这种机制下，maven还提供了一个类似java.lang.Object的顶级父pom.xml文件：

<project>
  <modelVersion>4.0.0</modelVersion>
  <name>Maven Default Project</name>
  <repositories>
    <repository>
      <id>central</id>
      <name>Maven Repository Switchboard</name>
      <layout>default</layout>
      <url>http://repo1.maven.org/maven2</url>
      <snapshots>
        <enabled>false</enabled>
      </snapshots>
    </repository>
  </repositories>
  <pluginRepositories>
    <pluginRepository>
      <id>central</id>
      <name>Maven Plugin Repository</name>
      <url>http://repo1.maven.org/maven2</url>
      <layout>default</layout>
      <snapshots>
        <enabled>false</enabled>
      </snapshots>
      <releases>
        <updatePolicy>never</updatePolicy>
      </releases>
    </pluginRepository>
  </pluginRepositories>
  <build>
    <directory>target</directory>
    <outputDirectory>target/classes</outputDirectory>
    <finalName>${project.artifactId}-${project.version}</finalName>
    <testOutputDirectory>target/test-classes</testOutputDirectory>
    <sourceDirectory>src/main/java</sourceDirectory>
    <scriptSourceDirectory>src/main/scripts</scriptSourceDirectory>
    <testSourceDirectory>src/test/java</testSourceDirectory>
    <resources>
      <resource>
        <directory>src/main/resources</directory>
      </resource>
    </resources>
    <testResources>
      <testResource>
        <directory>src/test/resources</directory>
      </testResource>
    </testResources>
    <pluginManagement>
       <plugins>
         <plugin>
           <artifactId>maven-antrun-plugin</artifactId>
           <version>1.1</version>
         </plugin>      
         <plugin>
           <artifactId>maven-assembly-plugin</artifactId>
           <version>2.2-beta-2</version>
         </plugin>
         <plugin>
           <artifactId>maven-clean-plugin</artifactId>
           <version>2.2</version>
         </plugin>
         <plugin>
           <artifactId>maven-compiler-plugin</artifactId>
           <version>2.0.2</version>
         </plugin>
         <plugin>
           <artifactId>maven-dependency-plugin</artifactId>
           <version>2.0</version>
         </plugin>
         <plugin>
           <artifactId>maven-deploy-plugin</artifactId>
           <version>2.3</version>
         </plugin>
         <plugin>
           <artifactId>maven-ear-plugin</artifactId>
           <version>2.3.1</version>
         </plugin>
         <plugin>
           <artifactId>maven-ejb-plugin</artifactId>
           <version>2.1</version>
         </plugin>
         <plugin>
           <artifactId>maven-install-plugin</artifactId>
           <version>2.2</version>
         </plugin>
         <plugin>
           <artifactId>maven-jar-plugin</artifactId>
           <version>2.2</version>
         </plugin>
         <plugin>
           <artifactId>maven-javadoc-plugin</artifactId>
           <version>2.4</version>
         </plugin>
         <plugin>
           <artifactId>maven-plugin-plugin</artifactId>
           <version>2.4.1</version>
         </plugin>
         <plugin>
           <artifactId>maven-rar-plugin</artifactId>
           <version>2.2</version>
         </plugin>
         <plugin>               
           <artifactId>maven-release-plugin</artifactId>
           <version>2.0-beta-7</version>
         </plugin>
         <plugin>               
           <artifactId>maven-resources-plugin</artifactId>
           <version>2.2</version>
         </plugin>
         <plugin>
           <artifactId>maven-site-plugin</artifactId>
           <version>2.0-beta-6</version>
         </plugin>
         <plugin>
           <artifactId>maven-source-plugin</artifactId>
           <version>2.0.4</version>
         </plugin>         
         <plugin>
            <artifactId>maven-surefire-plugin</artifactId>
            <version>2.4.2</version>
         </plugin>
         <plugin>
           <artifactId>maven-war-plugin</artifactId>
           <version>2.1-alpha-1</version>
         </plugin>
       </plugins>
     </pluginManagement>
  </build>
  <reporting>
    <outputDirectory>target/site</outputDirectory>
  </reporting>
  <profiles>
    <profile>
      <id>release-profile</id>
      <activation>
        <property>
          <name>performRelease</name>
          <value>true</value>
        </property>
      </activation>
      <build>
        <plugins>
          <plugin>
            <inherited>true</inherited>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-source-plugin</artifactId>
            <executions>
              <execution>
                <id>attach-sources</id>
                <goals>
                  <goal>jar</goal>
                </goals>
              </execution>
            </executions>
          </plugin>
          <plugin>
            <inherited>true</inherited>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-javadoc-plugin</artifactId>
            <executions>
              <execution>
                <id>attach-javadocs</id>
                <goals>
                  <goal>jar</goal>
                </goals>
              </execution>
            </executions>
          </plugin>
          <plugin>
            <inherited>true</inherited>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-deploy-plugin</artifactId>
            <configuration>
              <updateReleaseInfo>true</updateReleaseInfo>
            </configuration>
          </plugin>
        </plugins>
      </build>
    </profile>
  </profiles>
</project>

可以通过下面命令查看当前pom.xml受到超pom.xml文件的影响：

mvn help:effective-pom

聚合关系：用于将多个maven项目聚合为一个大的项目。

<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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.codehaus.mojo</groupId>
  <artifactId>my-parent</artifactId>
  <version>2.0</version>
  <modules>
    <module>my-project<module>
  </modules>
</project>

属性

maven的属性，是值的占位符，类似EL，类似ant的属性，比如${X}，可用于pom文件任何赋值的位置。有以下分类：

1. env.X：操作系统环境变量，比如${env.PATH}
2. project.x：pom文件中的属性，比如：<project><version>1.0</version></project>，引用方式：${project.version}
3. settings.x：settings.xml文件中的属性，比如：<settings><offline>false</offline></settings>，引用方式：${settings.offline}
4. Java System Properties：java.lang.System.getProperties()中的属性，比如java.home，引用方式：${java.home}
5. 自定义：在pom文件中可以：<properties><installDir>c:/apps/cargo-installs</installDir></properties>，引用方式：${installDir}

构建设置

构建有两种build标签：

<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/maven-v4_0_0.xsd">
  …
  <!– "Project Build" contains more elements than just the BaseBuild set –>
  <build>…</build>
  <profiles>
    <profile>
      <!– "Profile Build" contains a subset of "Project Build"s elements –>
      <build>…</build>
    </profile>
  </profiles>
</project>

build中的主要标签：Resources和Plugins。

Resources：用于排除或包含某些资源文件

    <resources>
      <resource>
        <targetPath>META-INF/plexus</targetPath>
        <filtering>false</filtering>
        <directory>${basedir}/src/main/plexus</directory>
        <includes>
          <include>configuration.xml</include>
        </includes>
        <excludes>
          <exclude>**/*.properties</exclude>
        </excludes>
      </resource>
    </resources>

Plugins：设置构建的插件

  <build>
    …
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-jar-plugin</artifactId>
        <version>2.0</version>
        <extensions>false</extensions>
        <inherited>true</inherited>
        <configuration>
          <classifier>test</classifier>
        </configuration>
        <dependencies>…</dependencies>
        <executions>…</executions>
      </plugin>