基于前两篇《Maven浅窥一：基础》和《Maven浅窥二：复杂项目》，应该已经可以创建Maven项目，甚至是较大的Maven项目。
然而，第一个经常遇到的问题是，通过archetype “maven-archetype-quickstart”(版本1.4)创建的project，都需要手动修改pom.xml。譬如，如果不想使用默认的junit 4.11而想使用junit 5，不得不每次都修改pom，更麻烦的，junit 4到junit 5是breaking change，所以只修改pom文件显然不够，还得修改默认的test文件，才能解决最起码的语法错误。
那么，archetype到底是个啥东东？查看官方文档：
Archetype is a Maven project templating toolkit. An archetype is defined as an original pattern or model from which all other things of the same kind are made
官方Lifecyle图：
说白了，archetype是个脚手架。跟Angular的”ng generate”类似，但是更原始且不会up to date。那么，如果想要避免每次都手工修改一大堆文件，创建一个local的archetype看起来是个不错的选择。
本文代码使用Github Repo： link
步骤一、创建一个基于archetype的空project
在想要创建的目录下，运行如下命令：
mvn -B archetype:generate -DgroupId="com.alvachien.app" -DartifactId="maven-tutorial-3" -DarchetypeArtifactId="maven-archetype-quickstart" -DarchetypeVersion="1.4"
这时，文件夹maven-tutorial-3应该被创建成功。
步骤二、修改POM以及相关的文件
修改POM.xml如下：
<?xml version="1.0" encoding="UTF-8"?>
<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.alvachien.learning</groupId>
<artifactId>maven-tutorial-3</artifactId>
<version>1.0-SNAPSHOT</version>
<name>maven-tutorial-3</name>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>11</java.version>
<junit.version>5.7.0</junit.version>
<!-- Plugin versions -->
<maven.shade>3.2.2</maven.shade>
<maven.clean>3.1.0</maven.clean>
<maven.resources>3.1.0</maven.resources>
<maven.compiler>3.8.1</maven.compiler>
<maven.surefire>3.0.0-M5</maven.surefire>
<maven.jar>3.2.0</maven.jar>
<maven.install>3.0.0-M1</maven.install>
<maven.deploy>2.8.2</maven.deploy>
<maven.site>3.7.1</maven.site>
<maven.compiler.source>${java.version}</maven.compiler.source>
<maven.compiler.target>${java.version}</maven.compiler.target>
<maven.compiler.release>${java.version}</maven.compiler.release>
</properties>
<dependencies>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>${maven.clean}</version>
</plugin>
<!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>${maven.resources}</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>${maven.compiler}</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>${maven.surefire}</version>
</plugin>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>${maven.jar}</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>${maven.install}</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>${maven.deploy}</version>
</plugin>
<!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>${maven.site}</version>
</plugin>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
<version>3.0.0</version>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
修改AppTest.java如下：
import static org.junit.jupiter.api.Assertions.assertTrue;
import org.junit.jupiter.api.Test;
public class AppTest {
@Test
public void shouldAnswerWithTrue() {
assertTrue(true);
}
}
步骤三、生成一个复用的archetype
运行如下命令：
mvn archetype:create-from-project
输出结果：
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 6.499 s
[INFO] Finished at: 2020-11-29T18:47:55+08:00
[INFO] ------------------------------------------------------------------------
[INFO] Archetype project created in D:\srccodes\git\learning-notes\maven-tutorial-3\target\generated-sources\archetype
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 11.063 s
[INFO] Finished at: 2020-11-29T18:47:55+08:00
[INFO] ------------------------------------------------------------------------
在对应的target目录，会有一个
target
└─generated-sources
└─archetype
└─src
├─main
│ └─resources
│ ├─archetype-resources
│ │ ├─.settings
│ │ ├─.vscode
│ │ └─src
│ │ ├─main
│ │ │ └─java
│ │ └─test
│ │ └─java
│ └─META-INF
│ └─maven
└─test
└─resources
└─projects
└─basic
步骤四、安装自定义的archetype到local repository
这时，在目录\target\generated-sources\archetype下，运行命令：
mvn install
该命令会将目录\target\generated-sources\archetype下的archetype.jar安装在local repository中。
Windows下，Local repository对应的目录为：C:\Users\ ~windows_user~ \ .m2\repository中。
该目录下会有一个archetype-catalog.xml文件，打开之后会发现其内容就是刚刚创建的archetype：
<?xml version="1.0" encoding="UTF-8"?>
<archetype-catalog xsi:schemaLocation="http://maven.apache.org/plugins/maven-archetype-plugin/archetype-catalog/1.0.0 http://maven.apache.org/xsd/archetype-catalog-1.0.0.xsd"
xmlns="http://maven.apache.org/plugins/maven-archetype-plugin/archetype-catalog/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<archetypes>
<archetype>
<groupId>com.alvachien.learning</groupId>
<artifactId>maven-tutorial-3-archetype</artifactId>
<version>1.0-SNAPSHOT</version>
<description>maven-tutorial-3-archetype</description>
</archetype>
</archetypes>
</archetype-catalog>
该文件夹下，\com\alvachien\learning\maven-tutorial-3-archetype内容如下：
C:.
│ maven-metadata-local.xml
│
└─1.0-SNAPSHOT
maven-metadata-local.xml
maven-tutorial-3-archetype-1.0-SNAPSHOT.jar
maven-tutorial-3-archetype-1.0-SNAPSHOT.pom
_remote.repositories
其中maven-metadata-local.xml文件：
<?xml version="1.0" encoding="UTF-8"?>
<metadata>
<groupId>com.alvachien.learning</groupId>
<artifactId>maven-tutorial-3-archetype</artifactId>
<versioning>
<versions>
<version>1.0-SNAPSHOT</version>
</versions>
<lastUpdated>20201129115103</lastUpdated>
</versioning>
</metadata>
步骤五、创建一个新project
在新的目录下，运行：
mvn archetype:generate -DarchetypeCatalog=local
这时系统会罗列当前local repository中所有的archetype：
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------< org.apache.maven:standalone-pom >-------------------
[INFO] Building Maven Stub Project (No POM) 1
[INFO] --------------------------------[ pom ]---------------------------------
[INFO]
[INFO] >>> maven-archetype-plugin:3.2.0:generate (default-cli) > generate-sources @ standalone-pom >>>
[INFO]
[INFO] <<< maven-archetype-plugin:3.2.0:generate (default-cli) < generate-sources @ standalone-pom <<<
[INFO]
[INFO]
[INFO] --- maven-archetype-plugin:3.2.0:generate (default-cli) @ standalone-pom ---
[INFO] Generating project in Interactive mode
[INFO] No archetype defined. Using maven-archetype-quickstart (org.apache.maven.archetypes:maven-archetype-quickstart:1.0)
Choose archetype:
1: local -> com.alvachien.learning:maven-tutorial-3-archetype (maven-tutorial-3-archetype)
Choose a number or apply filter (format: [groupId:]artifactId, case sensitive contains): :
按照提示可以继续创建project。打开生成的POM文件，就会发现所有的dependency都被正确设置。