适用人群
- 对maven有一些基本的概念，会一些日常的操作
- 希望深入了解maven的概念和机制，解释一些底层的细节
生命周期、阶段、插件、目标
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mvn clean dependency:copy-dependencies package
- 执行clean生命周期中clean阶段之前(包括)所有的阶段
- 执行 dependency插件copy-dependencies这个目标
- 执行default生命周期中package阶段之前(包括)所有的阶段
-
clean
<phases> <phase>pre-clean</phase> <phase>clean</phase> <phase>post-clean</phase> </phases> <default-phases> <clean> org.apache.maven.plugins:maven-clean-plugin:2.5:clean </clean> </default-phases> -
default
<phases> <phase>validate</phase> <phase>initialize</phase> <phase>generate-sources</phase> <phase>process-sources</phase> <phase>generate-resources</phase> <phase>process-resources</phase> <phase>compile</phase> <phase>process-classes</phase> <phase>generate-test-sources</phase> <phase>process-test-sources</phase> <phase>generate-test-resources</phase> <phase>process-test-resources</phase> <phase>test-compile</phase> <phase>process-test-classes</phase> <phase>test</phase> <phase>prepare-package</phase> <phase>package</phase> <phase>pre-integration-test</phase> <phase>integration-test</phase> <phase>post-integration-test</phase> <phase>verify</phase> <phase>install</phase> <phase>deploy</phase> </phases> -
site
<phases> <phase>pre-site</phase> <phase>site</phase> <phase>post-site</phase> <phase>site-deploy</phase> </phases> <default-phases> <site> org.apache.maven.plugins:maven-site-plugin:3.3:site </site> <site-deploy> org.apache.maven.plugins:maven-site-plugin:3.3:deploy </site-deploy> </default-phases>
不同打包类型绑定的阶段、插件和目标
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pom
<phases> <install> org.apache.maven.plugins:maven-install-plugin:2.4:install </install> <deploy> org.apache.maven.plugins:maven-deploy-plugin:2.7:deploy </deploy> </phases> -
jar
<phases> <process-resources> org.apache.maven.plugins:maven-resources-plugin:2.6:resources </process-resources> <compile> org.apache.maven.plugins:maven-compiler-plugin:3.1:compile </compile> <process-test-resources> org.apache.maven.plugins:maven-resources-plugin:2.6:testResources </process-test-resources> <test-compile> org.apache.maven.plugins:maven-compiler-plugin:3.1:testCompile </test-compile> <test> org.apache.maven.plugins:maven-surefire-plugin:2.12.4:test </test> <package> org.apache.maven.plugins:maven-jar-plugin:2.4:jar </package> <install> org.apache.maven.plugins:maven-install-plugin:2.4:install </install> <deploy> org.apache.maven.plugins:maven-deploy-plugin:2.7:deploy </deploy> </phases> -
war
<phases> <process-resources> org.apache.maven.plugins:maven-resources-plugin:2.6:resources </process-resources> <compile> org.apache.maven.plugins:maven-compiler-plugin:3.1:compile </compile> <process-test-resources> org.apache.maven.plugins:maven-resources-plugin:2.6:testResources </process-test-resources> <test-compile> org.apache.maven.plugins:maven-compiler-plugin:3.1:testCompile </test-compile> <test> org.apache.maven.plugins:maven-surefire-plugin:2.12.4:test </test> <package> org.apache.maven.plugins:maven-war-plugin:2.2:war </package> <install> org.apache.maven.plugins:maven-install-plugin:2.4:install </install> <deploy> org.apache.maven.plugins:maven-deploy-plugin:2.7:deploy </deploy> </phases>
POM(Project Object Model)
-
Super POM
- 位置 $MAVEN_HOME/lib/maven-model-builder-x.y.z.jar!/org/apache/maven/model/pom-4.0.0.xml
<project> <modelVersion>4.0.0</modelVersion> <repositories> <repository> <id>central</id> <name>Central Repository</name> <url>http://repo.maven.apache.org/maven2</url> <layout>default</layout> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>central</id> <name>Central Repository</name> <url>http://repo.maven.apache.org/maven2</url> <layout>default</layout> <snapshots> <enabled>false</enabled> </snapshots> <releases> <updatePolicy>never</updatePolicy> </releases> </pluginRepository> </pluginRepositories> <build> <directory>${project.basedir}/target</directory> <outputDirectory>${project.build.directory}/classes</outputDirectory> <finalName>${project.artifactId}-${project.version}</finalName> <testOutputDirectory>${project.build.directory}/test-classes</testOutputDirectory> <sourceDirectory>${project.basedir}/src/main/java</sourceDirectory> <scriptSourceDirectory>src/main/scripts</scriptSourceDirectory> <testSourceDirectory>${project.basedir}/src/test/java</testSourceDirectory> <resources> <resource> <directory>${project.basedir}/src/main/resources</directory> </resource> </resources> <testResources> <testResource> <directory>${project.basedir}/src/test/resources</directory> </testResource> </testResources> <pluginManagement> <!-- NOTE: These plugins will be removed from future versions of the super POM --> <!-- They are kept for the moment as they are very unlikely to conflict with lifecycle mappings (MNG-4453) --> <plugins> <plugin> <artifactId>maven-antrun-plugin</artifactId> <version>1.3</version> </plugin> <plugin> <artifactId>maven-assembly-plugin</artifactId> <version>2.2-beta-5</version> </plugin> <plugin> <artifactId>maven-dependency-plugin</artifactId> <version>2.1</version> </plugin> <plugin> <artifactId>maven-release-plugin</artifactId> <version>2.0</version> </plugin> </plugins> </pluginManagement> </build> <reporting> <outputDirectory>${project.build.directory}/site</outputDirectory> </reporting> <profiles> <!-- NOTE: The release profile will be removed from future versions of the super POM --> <profile> <id>release-profile</id> <activation> <property> <name>performRelease</name> <value>true</value> </property> </activation> <build> <plugins> <plugin> <inherited>true</inherited> <artifactId>maven-source-plugin</artifactId> <executions> <execution> <id>attach-sources</id> <goals> <goal>jar</goal> </goals> </execution> </executions> </plugin> <plugin> <inherited>true</inherited> <artifactId>maven-javadoc-plugin</artifactId> <executions> <execution> <id>attach-javadocs</id> <goals> <goal>jar</goal> </goals> </execution> </executions> </plugin> <plugin> <inherited>true</inherited> <artifactId>maven-deploy-plugin</artifactId> <configuration> <updateReleaseInfo>true</updateReleaseInfo> </configuration> </plugin> </plugins> </build> </profile> </profiles> </project>- 继承和聚合
<project> <modelVersion>4.0.0</modelVersion> <parent> <groupId>com.mycompany.app</groupId> <artifactId>my-app</artifactId> <version>1</version> </parent> <artifactId>my-module</artifactId> </project><project> <modelVersion>4.0.0</modelVersion> <groupId>com.mycompany.app</groupId> <artifactId>my-app</artifactId> <version>1</version> <packaging>pom</packaging> <modules> <module>my-module</module> </modules> </project> 内置properties
| value | evaluation result | common examples |
|---|---|---|
| project.* | POM content(参考 Super POM) |
|
| project.basedir | the directory containing the pom.xml file | ${project.basedir} |
| project.baseUri | the directory containing the pom.xml file as URI | ${project.baseUri} |
| build.timestamp maven.build.timestamp |
the UTC timestamp of build start, in yyyy-MM-dd'T'HH:mm:ss'Z' default format, which can be overridden with maven.build.timestamp.format POM property | ${maven.build.timestamp} |
| * | user properties, set from CLI with -Dproperty=value | ${skipTests} |
| * | model properties, such as project properties set in the pom | ${any.key} |
| maven.home | The path to the current Maven home. | ${maven.home} |
| maven.version | The version number of the current Maven execution (since 3.0.4). For example, "3.0.5". | ${maven.version} |
| maven.build.version | The full build version of the current Maven execution (since 3.0.4). For example, "Apache Maven 3.2.2 (r01de14724cdef164cd33c7c8c2fe155faf9602da; 2013-02-19T14:51:28+01:00)". | ${maven.build.version} |
| maven.repo.local | The repository on the local machine Maven shall use to store installed and downloaded artifacts (POMs, JARs, etc). | ${user.home}/.m2/repository |
| * | Java system properties(see JDK reference) |
|
| env.* * |
environment variables | ${env.PATH} |
| settings.* | Local user settings (see settings reference) | ${settings.localRepository} |
依赖管理
-
解决依赖冲突，最近原则
- D 1.0 生肖
A ├── B │ └── C │ └── D 2.0 └── E └── D 1.0- D 3.0 生效
A ├── B │ └── C │ └── D 2.0 ├── E │ └── D 1.0 │ └── D 3.0 │ └── D 4.0 -
scope
compile 默认类型 参与所有机制
provided 代表由环境提供，不用在打包时包含
runtime 只在运行时需要，不参与编译
test 只在测试代码中需要
system 类似provided 不从maven仓库拿包，从系统路径拿包
import 特殊类型，只导入dependencyManagement
不同类型的生效关系
scope\生效阶段 编译时 测试 运行时 传递依赖 compile ✓ ✓ ✓ ✓ provided ✓ ✓ ✕ ✕ runtime ✕ ✓ ✓ ✓ test ✕ ✓ ✕ ✕ system ✓ ✓ ✕ ✕ - 上层依赖scope与传递依赖冲突时的判定
上层scope\传递依赖 compile provided runtime test compile compile - runtime - provided provided - provided - runtime runtime - runtime - test test - test - -
type
- pom
- jar
- maven-plugin
- ebb
- war
- ear
- rar
- java-source
- javadoc
- ejb-client
- test-jar
-
classifier
- sources
- javadoc
- client
- tests
最小粒度依赖 {groupId, artifactId, type, classifier}
默认依赖 {groupId, artifactId, 'jar', null}
-
阻止传递依赖
- 被动: optional B->C(optional) A->B-✕(C)
- 主动: exclusion
仓库配置
-
仓库加载顺序
- $maven_home/conf/settings.xml
- $user_home/.m2/settings.xml
- local pom
- parent pom
- super pom
- dependency pom
-
镜像，替换某个(某些)仓库
- 替换中央仓库(mirrorOf)
<mirrors>
<mirror>
<id>other-mirror</id>
<name>Other Mirror Repository</name>
<url>https://other-mirror.repo.other-company.com/maven2</url>
<mirrorOf>central</mirrorOf>
</mirror>
</mirrors>
