手把手教你寫Maven的archetype項(xiàng)目腳手架

更新時(shí)間：2021年08月30日 11:40:14 作者：阿豪聊干貨

本文主要介紹了Maven的archetype項(xiàng)目腳手架，文中通過示例代碼介紹的非常詳細(xì)，具有一定的參考價(jià)值，感興趣的小伙伴們可以參考一下

一、背景

　　maven是一個(gè)很好的代碼構(gòu)建工具，采用“約定優(yōu)先于配置”的原則進(jìn)行項(xiàng)目管理，相信很多的java開發(fā)者應(yīng)該都了解maven并可能在工作當(dāng)中都是通過maven來管理項(xiàng)目的，在創(chuàng)建的項(xiàng)目的時(shí)候，我們往往會(huì)使用maven內(nèi)置的項(xiàng)目骨架也就是archetype來快速生成項(xiàng)目結(jié)構(gòu)。但是在一個(gè)團(tuán)隊(duì)做開發(fā)的過程中，可能僅僅依靠maven預(yù)先提供的archetyp可能是不夠的，團(tuán)隊(duì)之間協(xié)作有自己的定義方式，每個(gè)人的結(jié)構(gòu)定義風(fēng)格也不盡相同，在這樣的背景下我們有必要去定義一個(gè)統(tǒng)一的代碼骨架供團(tuán)隊(duì)使用，這樣做的好處是當(dāng)團(tuán)隊(duì)需要開始一個(gè)新項(xiàng)目的時(shí)候，可以利用自定義的maven骨架一鍵生成項(xiàng)目。

　　archetype是在maven-archetype-plugin插件執(zhí)行g(shù)enerate目標(biāo)的時(shí)候進(jìn)行配置的，我們經(jīng)常使用到maven的內(nèi)嵌的骨架包括：maven-archetype-webapp、maven-archetype-quickstart。前者用來快速搭建一個(gè)web工程項(xiàng)目，后者用來快速搭建一個(gè)普通的java工程項(xiàng)目。

二、手寫普通單模塊項(xiàng)目的archetype

單模塊項(xiàng)目的archetype腳手架項(xiàng)目的結(jié)構(gòu)

上圖中的各個(gè)文件詳解：

根目錄beast-archetype下的pom.xml和一般的maven項(xiàng)目一樣主要定義archetype項(xiàng)目的坐標(biāo)等信息。
所有的項(xiàng)目骨架內(nèi)容都集中在src/main/resources/archetype-resources文件夾下。
archetype-resources中的pom.xml定義了待生成項(xiàng)目的pom文件的內(nèi)容，/src/main/java、/src/test/java中分別定義了待生成項(xiàng)目中相應(yīng)目錄下的內(nèi)容
/src/main/resources/META-INF/maven/archetype-metadata.xml中定義相關(guān)的元數(shù)據(jù)描述(其中該文件的位置固定為resources/META-INF/maven文件夾下,且名稱固定為archetype-metadata.xml)。

1.beast-archetype/pom.xml內(nèi)容如下

<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.thebeastshop</groupId>
    <artifactId>beast-archetype</artifactId>
    <version>1.1</version>
    <packaging>jar</packaging>

    <name>beast-archetype</name>
    <url>http://maven.apache.org</url>

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

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <build>
        <finalName>beast-archetype</finalName>
    </build>
</project>

2.src/main/resources/archetype-resources/pom.xml內(nèi)容如下：

<?xml version="1.0"?>
<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>${groupId}</groupId>
    <artifactId>${artifactId}</artifactId>
    <version>${version}</version>
    <name>${artifactId}</name>
    
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
             <plugin> 
                 <artifactId>maven-deploy-plugin</artifactId> 
                 <configuration> 
                    <skip>true</skip> 
                 </configuration> 
             </plugin>
        </plugins>
        <pluginManagement>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-archetype-plugin</artifactId>
                    <version>2.2</version>
                    <configuration>
                        <source>1.7</source>
                        <target>1.7</target>
                    </configuration>
                </plugin>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-source-plugin</artifactId>
                    <configuration>
                        <encoding>UTF-8</encoding>
                    </configuration>
                </plugin>
            </plugins>
        </pluginManagement>
    </build>
</project>

其中：上面${}標(biāo)識的變量都是通過maven中的命令行傳進(jìn)來的，如：mvn archetype:generate -DgroupId=com.thebeastshop

3.src/main/resources/META-INF/maven/archetype-metadata.xml內(nèi)容如下：

<?xml version="1.0" encoding="UTF-8"?>
<archetype-descriptor  name="beast-archetype"
        xmlns="http://maven.apache.org/plugins/maven-archetype-plugin/archetype-descriptor/1.0.0"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="
            http://maven.apache.org/plugins/maven-archetype-plugin/archetype-descriptor/1.0.0
            http://maven.apache.org/xsd/archetype-descriptor-1.0.0.xsd">

    <requiredProperties>
        <requiredProperty key="package-name" />
    </requiredProperties>

    <fileSets>
        <fileSet filtered="true" packaged="true" encoding="UTF-8">
            <directory>src/main/java</directory>
            <includes>
                <include>**/*.java</include>
            </includes>
        </fileSet>
        <fileSet filtered="true" encoding="UTF-8">
            <directory>src/main/resources</directory>
            <includes>
                <include>**/*.*</include>
            </includes>
        </fileSet>
        <fileSet filtered="true" packaged="true" encoding="UTF-8">
            <directory>src/test/java</directory>
            <includes>
                <include>**/*.java</include>
            </includes>
        </fileSet>
        <fileSet encoding="UTF-8">
            <directory>src/test/resources</directory>
            <includes>
                <include>**/*.*</include>
            </includes>
        </fileSet>
    </fileSets>
</archetype-descriptor>

說明：

packaged="true"標(biāo)識src/main/resources/archetype-resources/src/main/java中對應(yīng)的內(nèi)容是否要放入到package中,比如package為com.thebeastshop,那么如果該屬性為true,則對應(yīng)的java文件會(huì)放到com/thebeastshop文件夾下，也就是包路徑下。
filtered="true"標(biāo)識下面提到的${}是否要進(jìn)行替換

4.src/main/resources/archetype-resources/src/main/java/Demo.java內(nèi)容如下：

package ${package};

public class Demo{
    public static void main( String[] args )
    {
        System.out.println( "Hello My Archetype!" );
    }
}

5.這樣我們就手寫好了一個(gè)自定義的maven的archetype骨架項(xiàng)目，我們只需要通過mvn clean install 命令把該jar包安裝到本地倉庫，然后通過本地倉庫中的該jar包來生成一個(gè)項(xiàng)目看看效果，使用如下命令：

 mvn archetype:generate 
　　-DgroupId=comthebeastshop 
　　-DartifactId=beast-test 
　　-Dpackage="com.thebeastshop.test" 
　　-DarchetypeGroupId=com.thebeastshop 
　　-DarchetypeArtifactId=beast-archetype -DarchetypeVersion=1.1 -X -DarchetypeCatalog=local

三、手寫maven多module的項(xiàng)目骨架archetype

1.多模塊骨架項(xiàng)目的項(xiàng)目結(jié)構(gòu)

這跟單模塊項(xiàng)目區(qū)別不大，但是有幾個(gè)概念需要說明：

“__rootArtifactId__”占位符會(huì)被parent項(xiàng)目的artifactId替換
${rootArtifactId}也會(huì)被parent項(xiàng)目的artifactId替換
src/main/resources/archetype-resources里必須要有一個(gè)頂級pom文件（如果是單工程就是工程pom文件），同時(shí)子文件夾代表了模塊定義

2.模板工程定義描述文件

META-INF/maven/archetype-metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<archetype-descriptor  name="beast-archetype"
        xmlns="http://maven.apache.org/plugins/maven-archetype-plugin/archetype-descriptor/1.0.0"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="
            http://maven.apache.org/plugins/maven-archetype-plugin/archetype-descriptor/1.0.0
            http://maven.apache.org/xsd/archetype-descriptor-1.0.0.xsd">

    <requiredProperties>
        <requiredProperty key="groupId">
            <defaultValue>com.thebeastshop</defaultValue>
        </requiredProperty>
        <requiredProperty key="artifactId">
            <defaultValue>test</defaultValue>
        </requiredProperty>
        <requiredProperty key="package">
            <defaultValue>com.thebeastshop.test</defaultValue>
        </requiredProperty>
    </requiredProperties>

    <modules>
        <module id="${rootArtifactId}-api" name="${rootArtifactId}-api" dir="__rootArtifactId__-api">
            <fileSets>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/main/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/test/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/main/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/test/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
            </fileSets>
        </module>
        <module id="${rootArtifactId}-core" name="${rootArtifactId}-core" dir="__rootArtifactId__-core">
            <fileSets>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/main/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/test/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet filtered="true" encoding="UTF-8">
                    <directory>src/main/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/test/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
            </fileSets>
        </module>
        <module id="${rootArtifactId}-dao" name="${rootArtifactId}-dao" dir="__rootArtifactId__-dao">
            <fileSets>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/main/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/test/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet filtered="true" encoding="UTF-8">
                    <directory>src/main/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                        <include>mapper</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/test/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
            </fileSets>
        </module>
        <module id="${rootArtifactId}-main" name="${rootArtifactId}-main" dir="__rootArtifactId__-main">
            <fileSets>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/main/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/test/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet filtered="true" encoding="UTF-8">
                    <directory>src/main/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/test/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/main/assembly</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/main/bin</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
            </fileSets>
        </module>
        <module id="${rootArtifactId}-mybatisGen" name="${rootArtifactId}-mybatisGen" dir="__rootArtifactId__-mybatisGen">
            <fileSets>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/main/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet filtered="true" encoding="UTF-8" packaged="true">
                    <directory>src/test/java</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/main/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
                <fileSet encoding="UTF-8">
                    <directory>src/test/resources</directory>
                    <includes>
                        <include>**/*.*</include>
                    </includes>
                </fileSet>
            </fileSets>
        </module>
    </modules>
</archetype-descriptor>

屬性變量定義

<requiredProperties>
    <requiredProperty key="groupId">
        <defaultValue>com.thebeastshop</defaultValue>
    </requiredProperty>
    <requiredProperty key="artifactId">
        <defaultValue>test</defaultValue>
    </requiredProperty>
    <requiredProperty key="package">
        <defaultValue>com.thebeastshop.test</defaultValue>
    </requiredProperty>
</requiredProperties>

這些屬性可以在資源元文件里的任意一個(gè)文件里通過${var}來引用，所以的元文件最終都可以選擇通過velocity引擎來執(zhí)行替換后生成。
默認(rèn)的屬性有：groupId，artifactId，packeage，version等

項(xiàng)目子模塊定義

<modules>
    <module id="${rootArtifactId}-api" name="${rootArtifactId}-api" dir="__rootArtifactId__-api">
        ...
    </module>
    <module id="${rootArtifactId}-core" name="${rootArtifactId}-core" dir="__rootArtifactId__-core">
        ...
    </module>
    <module id="${rootArtifactId}-dao" name="${rootArtifactId}-dao" dir="__rootArtifactId__-dao">
        ...
    </module>
    <module id="${rootArtifactId}-main" name="${rootArtifactId}-main" dir="__rootArtifactId__-main">
        ...
    </module>
    <module id="${rootArtifactId}-mybatisGen" name="${rootArtifactId}-mybatisGen" dir="__rootArtifactId__-mybatisGen">
        ...
    </module>
</modules>

module有三個(gè)屬性，解釋如下：

id ：定義子模塊工程的artifactId.
dir ：子模塊工程源文件在archetype-resources里對應(yīng)的directory.
name ：子模塊的名字.

3.子模塊pom.xml定義如下(以core模塊為例)：

<?xml version="1.0"?>
<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.thebeastshop</groupId>
        <artifactId>${rootArtifactId}</artifactId>
        <version>${version}</version>
    </parent>

    <artifactId>${artifactId}</artifactId>
    <name>${artifactId}</name>
    
    <dependencies>
        <dependency>
            <groupId>com.thebeastshop</groupId>
            <artifactId>${rootArtifactId}-api</artifactId>
            <version>${api.version}</version>
        </dependency>
        <dependency>
            <groupId>com.thebeastshop</groupId>
            <artifactId>${rootArtifactId}-dao</artifactId>
            <version>${project.parent.version}</version>
        </dependency>
    </dependencies>
    
    <build>
        <plugins>
             <plugin> 
                 <artifactId>maven-deploy-plugin</artifactId> 
                 <configuration> 
                    <skip>true</skip> 
                 </configuration> 
             </plugin>
        </plugins>
    </build>
</project>

其中${rootArtifactId}就代表父項(xiàng)目的artifactId.

4.我們和單模塊腳手架工程一樣，通過mvn clean install命令把該腳手架項(xiàng)目安裝到本地maven倉庫，然后就可以使用該項(xiàng)目來快速生成新項(xiàng)目結(jié)構(gòu)了，生成命令如下：

mvn archetype:generate 
　　-DgroupId=com.thebeastshop 
　　-DartifactId=ddd 
　　-Dversion=1.0.0-SNAPSHOT
　　-DarchetypeGroupId=com.thebeastshop 
　　-DarchetypeArtifactId=beast-archetype 
　　-DarchetypeVersion=1.3-SNAPSHOT -X -DarchetypeCatalog=local

我們就會(huì)看到生成好的項(xiàng)目結(jié)構(gòu)如下：