Maven实战

bin：包含了运行的脚本文件，包括<br>shell脚本和bat脚本（新版更新成了cmd脚本）

boot：一个类加载器框架，提供了更加丰富的语法

conf：里面的settings.xml可以全局控制Maven的行为

lib：包含了Maven运行时需要的Java类库

默认包含Maven的本地仓库.m2/repository

groupId、artifactId、version这三个元素定义了一个项目基本的坐标

主代码位于 src/main/java目录

测试代码位于 src/test/java目录

当没有在POM中指定打包类型时，使用默认的jar进行打包

如果希望其他的Maven项目引用，需要使用 mvn install 这个命令

mvn &nbsp;archetype : generate

如果希望其他的Maven项目引用，需要使用 mvn install 这个命令

包含groupId、artifactId、version、packaging、classifier

packaging：有jar、war等。缺省值为：jar

classifier： 定义一些附属构建，不能直接定义项目的classifier，是由附加的插件帮助生成的

&lt;dependencies&gt;下&lt;dependency&gt;标签<br>groupId、artifactId、version坐标<br>type：依赖的类型<br>scope：依赖的范围<br>optional：标记依赖是否可选<br>exclusions：排除传递性依赖

有三种classpath（编译classpath、测试classpath、运行classpath）

compile：编译依赖范围，对三种classpath都有效；<br>test：测试依赖范围，只对测试classpath有效；<br>provided：已提供依赖范围，只对编译和测试classpath有效；<br>runtime：运行时依赖范围，对测试、运行classpath有效；<br>system：系统依赖范围，只对编译和测试classpath有效。（这种依赖是不通过maven仓库找依赖包的，会从systemPath指定的路径中寻找依赖包，所以不具备移植性）<br>import：导入依赖范围。

传递性依赖的又意思就是：A-&gt;B,B-&gt;C,=&gt;A-&gt;C

------------------------------------------------------------<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; compile &nbsp; &nbsp; &nbsp; &nbsp;test &nbsp; &nbsp; &nbsp; &nbsp;provided &nbsp; &nbsp; &nbsp; &nbsp;runtime &nbsp; &nbsp; &nbsp;<br>------------------------------------------------------------<br>compile &nbsp; &nbsp; compile &nbsp; &nbsp; &nbsp; &nbsp;—— &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; —— &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; runtime<br>&nbsp; &nbsp;test &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;test &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;—— &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; —— &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; test<br>provided &nbsp; &nbsp;provided &nbsp; &nbsp; &nbsp;—— &nbsp; &nbsp; &nbsp; &nbsp; provided &nbsp; &nbsp; &nbsp;provided<br>runtime &nbsp; &nbsp; &nbsp;runtime &nbsp; &nbsp; &nbsp; &nbsp;—— &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; —— &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; runtime

依赖调节第一原则：路径最近者优先<br>依赖调节第二原则：第一声明者优先（也就是在POM先定义的先依赖）

A-&gt;B, B-&gt;可选C, B-&gt;可选D， 则 &nbsp;C,D不会被传递依赖给A

排除依赖：&lt;exclusions&gt;下的&lt;exclusion&gt;标签

归类依赖：&lt;properties&gt;中定义一个元素test，以后需要的地方直接引用${test}

优化依赖：mvn dependency：list &nbsp;查看当前项目已解析依赖<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;mvn dependency：tree 查看依赖树<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;mvn dependency：analyze 分析依赖树

在某个统一的位置存储所有的Maven项目构件，这个统一的位置就是仓库

根据构件的坐标定义存储路径

本地仓库：&lt;localRepository&gt;&lt;/localRepository&gt;

mvn clean install 命令会将当前构件安装到本地仓库中去

在Pom文件中配置远程仓库&lt;repository&gt;...&lt;/repository&gt;

releases和snapshots包含 updatePolicy和checksumPolicy :<br>updatePolicy：表示maven从远程仓库检查更新的频率。（never，默认always，interval:X每个x分钟检查）<br>checksumPolicy：下载artifact时，进行文件校验。(默认warn，fail，ignore)

在settings.xml文件中添加&lt;server&gt;...&lt;/servers&gt;中的&lt;id&gt;&lt;/id&gt;会和Pom中的仓库对应

部署artifact至远程仓库：&lt;distributionManagement&gt;...&lt;/distributionManagement&gt;<br>部署artifact命令：mvn clean deploy

快照版本：snapshot，maven会自动加上版本号<br>当有依赖时，maven会自定进行最新版本的artifact下载，maven默认每天检查一次，也就是仓库的updatePolicy属性，也可以使用 mvn clean install-U 属性强制检查更新

1.2这种显示版本：本地仓库---&gt; 远程仓库<br>-----------------------------------------------------------------------------------------------------<br>release和latest：读取所有远程仓库元数据maven-metadata.xml---&gt;与本地仓库元数据合并---&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;计算release和latest的真实值---&gt;本地仓库寻找---&gt;远程仓库寻找---&gt;将真实值 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;替换成release和latest，修改artifact名字并使用<br>-----------------------------------------------------------------------------------------------------<br>snapshot：读取所有远程仓库元数据maven-metadata.xml---&gt;与本地仓库元数据合并---&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 计算snapshot的真实值---&gt;本地仓库寻找---&gt;远程仓库寻找---&gt;替换成release和lates &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; t，修改artifact名字并使用

在settings配置文件中添加&lt;mirror&gt;...&lt;/mirror&gt;<br>&lt;mirrorOf&gt;id&lt;/mirrorOf&gt;表示仓库劫持，任何对id仓库的访问都会劫持到镜像仓库中去

maven的生命周期：清理、初始化、编译、测试、打包、集成测试、验证、部署、站点生成

maven的生命周期本身不做任何工作，实际工作（如编译）是由插件来完成的

maven有三套生命周期，clean：清理项目、default：构建项目、site：建立项目站点

每个生命周期包含一些phase（阶段），后面的phase依赖于前面的phase

clean生命周期：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;pre-clean：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;clean：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;post-clean：

default生命周期：validate：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; initialize：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; generate-sources：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; process-sources：处理项目主资源文件。对/src/main/resources目录的内容进 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;行变量替换，复制到项目输出的主ClassPath目录中<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; generate-resources：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; process-resources：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; compile：编译项目的主源码。src/main/java<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; process-classes：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; generate-test-sources：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; process-test-sources：处理项目测试资源文件。src/test/resources<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; generate-test-resources：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; process-test-resources：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; test-compile：编译项目的测试代码。src/test/java<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; process-test-classes：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; test：使用单元测试框架进行测试，测试代码不会打包和部署<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; prepare-package：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; papckage：使用编译好的代码，打包成可发布的版本，如JAR<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; pre-integration-test：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; integration-test：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; post-integration-test：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; verify：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; install：将包安装到Maven本地仓库，供本地其他项目使用<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; deploy：将artifact复制到远程仓库，供其他项目使用

site生命周期：建立和发布项目站点<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; pre-site：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; site：生成项目站点文档<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; post-site：<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; site-deploy：将生成的项目站点发布到服务器上<br>

多个功能聚集在一个插件里，每个功能对应一个插件的目标：<br>ie. dependency:anlyze---&gt;分析项目依赖<br>&nbsp; &nbsp; &nbsp;dependency:tree---&gt;画出项目的依赖树<br>&nbsp; &nbsp; &nbsp;dependency:list---&gt;列出项目的依赖

生命周期的phase与plugin 的goal绑定在一起完成工作，<br>ie，default的compile与maven-compiler-plugin：compile目标绑定在一起

内置的绑定：clean<br>------------------------------------------------------------<br>&nbsp; &nbsp; &nbsp; &nbsp; 生命周期阶段 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;插件目标 &nbsp; &nbsp; &nbsp;<br>------------------------------------------------------------<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;pre-clean &nbsp; &nbsp; &nbsp; &nbsp;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; clean &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;maven-clean-plugin:clean<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;post-clean

内置的绑定：site<br>------------------------------------------------------------<br>&nbsp; &nbsp; &nbsp; &nbsp; 生命周期阶段 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;插件目标 &nbsp; &nbsp; &nbsp;<br>------------------------------------------------------------<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;pre-clean &nbsp; &nbsp; &nbsp; &nbsp;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; site &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;maven-site-plugin:site<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;post-site<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;site-deploy &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;maven-site-plugin:deploy

内置的绑定：default（jar）<br>----------------------------------------------------------------------------------------------<br>&nbsp; &nbsp; &nbsp; &nbsp; 生命周期阶段 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;插件目标 &nbsp; &nbsp; &nbsp;<br>----------------------------------------------------------------------------------------------<br>&nbsp; &nbsp; &nbsp;process-resources &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; maven-resources-plugin : resources<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;compile &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; maven-compiler-plugin : compile<br>&nbsp; &nbsp;process-test-resources &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;maven-resources-plugin : testResources<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;test-compile &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; maven-compiler-plugin : testCompile<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; test &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;maven-surefire-plugin : test<br>&nbsp; &nbsp; &nbsp; &nbsp; package &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; maven-jar-plugin : jar<br>&nbsp; &nbsp; &nbsp; &nbsp; install &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; maven-install-plugin : install<br>&nbsp; &nbsp; &nbsp; &nbsp; deploy &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;maven-deploy-plugin : deploy

自定义绑定：&lt;bulid&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;plugins&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;plugin&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;executions&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;execution&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;id&gt;...&lt;/id&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;phase&gt;...&lt;/phase&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;goals&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;goal&gt;...&lt;/goal&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;/goals&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;/execution&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/executions&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;/plugin&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/plugins&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;/build&gt;<br>当多个 plugin：goals 绑定到 同一个phase时，按照绑定的顺序执行

命令行插件配置：-Dkey=value &nbsp; ig：mvn install -Dmaven.test.skip=true

POM插件配置：当configuration放在&lt;plugin&gt;下时，表示这个是全局配置<br>在&lt;plugin&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;configuration&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;......<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;/configuration&gt;<br>&nbsp; &nbsp; &lt;/plugin&gt;

POM中插件任务配置：当configuration放在&lt;execution&gt;下时，表示这个是特定任务<br>&nbsp; &nbsp;&lt;execution&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &lt;configuration&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &lt;/configuration&gt;<br>&nbsp; &nbsp;&lt;/execution&gt;

在线插件信息

使用maven-help-plugin 描述插件：<br>mvn help：describe

mvn dependency：tree<br>之所以可以使用dependency代替groupId：artifactId：version，是因为后者artifactId的前缀的值是前者

插件仓库：<br>&lt;pluginRepositories&gt;<br>&nbsp; &nbsp; &nbsp; &lt;pluginRepository&gt;<br>&nbsp; &nbsp; &nbsp; &lt;/pluginRepository&gt;<br>&lt;/pluginRepositories&gt;<br>

插件的默认groupId：<br>若插件为Maven的官方插件，则在POM配置中可以省略groupId的值org.apache.maven.plugins

解析插件版本：<br>1，在super POM中设定了核心插件的版本，当用户使用核心插件时，不指定版本，就会使用 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;super &nbsp;POM中的版本<br>2，若使用了非核心插件，且没有指定版本，则会检查所有插件仓库中的版本，解析到最新的 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;release版本（maven2 会解析至latest，maven3 会解析至release）

解析插件前缀：<br>1，会查询groupId/maven-metadata.xml<br>2，groupId默认的值为：org.apache.maven.plugins 和 org.codehaus.mojo（因为大部分的插件 &nbsp; &nbsp; &nbsp;都是这两个仓库开发的）<br>3，如果想在检查其他的仓库元数据，在settings.xml中添加 <br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;settings&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;pluginGroups&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;pluginGroup&gt;......&lt;/pluginGroup&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/pluginGroups&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/settings&gt;

创建一个额外的聚合maven项目，包含多个maven项目，这样就可以统一构建多个maven项目<br>聚合的maven项目&lt;packaging&gt;pom&lt;/packaging&gt;（packaging的打包方式必须为pom）<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;modules&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;module&gt;maven项目一（相对路径）&lt;/module&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;module&gt;maven项目二（相对路径）&lt;/module&gt;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;/modules&gt;

聚合项目与其他maven项目即可以是父子关系，也可以是平行关系，只需要&lt;module&gt;相对路径配置正确即可

可以将子模块中公共的部分提取出来，放到父模块中。

父模块的打包方式为pom，子模块的pom中需要继承父模块的pom<br><div>&lt;parent&gt;</div><div>&nbsp; &nbsp; &lt;groupId&gt;...&lt;/groupId&gt;</div><div>&nbsp; &nbsp; &lt;artifactId&gt;...&lt;/artifactId&gt;</div><div>&nbsp; &nbsp; &lt;version&gt;...&lt;/version&gt;</div><div>&nbsp; &nbsp; &lt;relativePath&gt;../account-parent/pom.xml（相对路径）&lt;/relativePath&gt;</div><div>&nbsp; &lt;/parent&gt;</div>

可以继承的pom元素：<br>groupId：项目组ID<br>version：项目的版本<br>description：项目的描述信息<br>organization：项目的组织信息<br>inceptionYear：项目的创始年份<br>url：项目的URL地址<br>developers：项目的开发者信息<br>contributors：项目的贡献者信息<br>distributionManagement：项目的部署配置<br>issueManagement：项目的缺陷跟踪系统信息<br>ciManagement：项目的持续集成系统信息<br>scm：项目版本控制信息<br>mailingLists：项目的邮件列表信息<br>properties：自定义的maven属性<br>dependencies：项目的依赖配置<br>dependencyManagement：项目的依赖管理配置<br>repositories：项目仓库地址配置<br>build：项目源码目录配置、输出目录配置、插件配置、插件管理配置<br>reporting：项目的报告输出目录配置、报告插件配置

1，dependencyManagement元素能让子模块继承到父模块的依赖配置，在dependencyManagement中声明的依赖不会引入实际的依赖。可以在父模块的dependencyManagement中添加如下配置：<br><div>&lt;dependencyManagement&gt;</div><div>&nbsp; &nbsp; &lt;dependencies&gt;</div><div>&nbsp; &nbsp; &lt;dependency&gt;</div><div>&nbsp; &nbsp; &nbsp; &lt;groupId&gt;org.springframework&lt;/groupId&gt;</div><div>&nbsp; &nbsp; &nbsp; &lt;artifactId&gt;spring-core&lt;/artifactId&gt;</div><div>&nbsp; &nbsp; &nbsp; &lt;version&gt;${springframework.version}&lt;/version&gt;</div><div>&nbsp; &nbsp; &lt;/dependency&gt;</div><div>&nbsp; &nbsp; &lt;/dependencies&gt;</div><div>&nbsp; &lt;/dependencyManagement&gt;<br>子模块需要使用这个依赖时：<br><div>&lt;dependency&gt;</div><div>&nbsp; &nbsp; &nbsp; &lt;groupId&gt;org.springframework&lt;/groupId&gt;</div><div>&nbsp; &nbsp; &nbsp; &lt;artifactId&gt;spring-core&lt;/artifactId&gt;</div><div>&nbsp; &nbsp; &lt;/dependency&gt;<br>虽然相比于之前，只少了版本这一行，但是可以统一整个项目中的依赖版本号。推荐使用<br><br>2，当想在另外一个项目中使用相同的dependencyManagement时，可以使用import范围依赖:<br>&lt;dependency&gt;<br>&nbsp; &nbsp; &lt;groupId&gt;...&lt;/groupId&gt;<br>&nbsp; &nbsp; &lt;artifactId&gt;...&lt;/artifactId&gt;<br>&nbsp; &nbsp; &lt;version&gt;...&lt;/version&gt;<br>&nbsp; &nbsp; &lt;type&gt;pom&lt;/type&gt;（type只能是pom类型）<br>&nbsp; &nbsp; &lt;scope&gt;import&lt;/scope&gt;<br>&lt;/dependency&gt;</div></div>

插件管理：<br>pluginManagement元素集中管理插件，xml配置文件信息如上

聚合与继承的关系：<br>&nbsp; &nbsp; 聚合：聚合模块知道哪些被聚合的模块，但被聚合的模块不知道聚合模块的存在<br>&nbsp; &nbsp; 继承：父POM不知道子模块，但子模块都知道父POM的存在<br><br>可以将聚合和继承的代码都放到同一个pom文件中

约定优于配置：<br>&nbsp; &nbsp;&nbsp;

反应堆的构建顺序：<br>&nbsp; &nbsp; &nbsp;1，maven按顺序读取pom，如果该pom没有依赖模块，那么就构建该模块<br>&nbsp; &nbsp; &nbsp;2，否则就先构建其依赖的模块<br>&nbsp; &nbsp; &nbsp;3，如果该依赖还依赖其它的模块，则进一步先构建依赖的依赖

裁剪反应堆：<br>&nbsp; &nbsp; &nbsp;1，-am（--also-make）：构建所列模块的依赖模块<br>&nbsp; &nbsp; &nbsp;2，-amd(--also-make-dependents)：构建所列模块的依赖模块，构建依赖于依赖模块的其它 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;模块<br>&nbsp; &nbsp; &nbsp;3，-pl(--projects)：构建指定的模块，模块间用逗号隔开<br>&nbsp; &nbsp; &nbsp;4, &nbsp;-rf(--resume-from)：在完整的反应堆上，指定从哪个模块开始往后构建

org.apache.maven.archetypes:maven-archetype-webapp

org.apache.maven.archetypes:maven-archetype-webapp