Maven 项目模板
Maven 使用 archetype(原型) 来创建自定义的项目结构,形成 Maven 项目模板。
在前面章节我们学到 Maven 使用下面的命令来快速创建 java 项目:
$ mvn archetype:generate
什么是 archetype?
archetype 也就是原型,是一个 Maven 插件,准确说是一个项目模板,它的任务是根据模板创建一个项目结构。我们将使用 quickstart 原型插件创建一个简单的 java 应用程序。
使用项目模板
让我们打开命令控制台,跳转到 /workspace/java 目录并执行以下 mvn 命令:
$ mvn archetype:generate
Maven 将开始处理,并要求选择所需的原型:
[INFO] Scanning for projects...
[INFO] Searching repository for plugin with prefix: 'archetype'.
[INFO] -------------------------------------------------------------------
[INFO] Building Maven Default Project
[INFO]task-segment: [archetype:generate] (aggregator-style)
[INFO] -------------------------------------------------------------------
[INFO] Preparing archetype:generate
...
3046: remote -> us.fatehi:schemacrawler-archetype-maven-project (-)
3047: remote -> us.fatehi:schemacrawler-archetype-plugin-command (-)
3048: remote -> us.fatehi:schemacrawler-archetype-plugin-dbconnector (-)
3049: remote -> us.fatehi:schemacrawler-archetype-plugin-lint (-)
3050: remote -> ws.osiris:osiris-archetype (Maven Archetype for Osiris)
3051: remote -> xyz.luan.generator:xyz-gae-generator (-)
3052: remote -> xyz.luan.generator:xyz-generator (-)
3053: remote -> za.co.absa.hyperdrive:component-archetype (-)
3054: remote -> za.co.absa.hyperdrive:component-archetype_2.11 (-)
3055: remote -> za.co.absa.hyperdrive:component-archetype_2.12 (-)
Choose a number or apply filter (format: [groupId:]artifactId, case sensitive contains): 1870: Choose org.apache.maven.archetypes:maven-archetype-quickstart version:
按下 Enter 选择默认选项 (1870:maven-archetype-quickstart)。
Maven 将询问原型的版本
Choose a number or apply filter (format: [groupId:]artifactId, case sensitive contains): 1870: Choose org.apache.maven.archetypes:maven-archetype-quickstart version:
1: 1.0-alpha-1
2: 1.0-alpha-2
3: 1.0-alpha-3
4: 1.0-alpha-4
5: 1.0
6: 1.1
7: 1.3
8: 1.4
Choose a number: 8:
按下 Enter 选择默认选项 (8:maven-archetype-quickstart:1.4)
Maven 将询问项目细节。按要求输入项目细节。如果要使用默认值则直接按 Enter 键。你也可以输入自己的值。
Define value for property 'groupId': : com.companyname.insurance
Define value for property 'artifactId': : health
Define value for property 'version': 1.0-SNAPSHOT
Define value for property 'package': com.companyname.insurance
Maven 将要求确认项目细节,按 Enter 或按 Y
Confirm properties configuration:
groupId: com.companyname.insurance
artifactId: health
version: 1.0-SNAPSHOT
package: com.companyname.insurance
Y:
现在 Maven 将开始创建项目结构,显示如下:
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Archetype: maven-archetype-quickstart:1.4
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: com.companyname.insurance
[INFO] Parameter: artifactId, Value: health
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: package, Value: com.companyname.insurance
[INFO] Parameter: packageInPathFormat, Value: com/companyname/insurance
[INFO] Parameter: package, Value: com.companyname.insurance
[INFO] Parameter: groupId, Value: com.companyname.insurance
[INFO] Parameter: artifactId, Value: health
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Project created from Archetype in dir: /Users/liuhanzeng/workspace/java/health
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 04:53 min
[INFO] Finished at: 2022-03-04T15:19:14+08:00
[INFO] ------------------------------------------------------------------------
[WARNING] The requested profile "test" could not be activated because it does not exist.
创建的项目
现在转到 /workspace/java 目录。你会看到一个名为 health 的 java 应用程序项目,就像在项目创建的时候建立的 artifactId 名称一样。 Maven 将创建一个有标准目录布局的项目,如下所示:
创建 pom.xml
Maven 为项目自动生成一个 pom.xml文件,如下所示:
<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.companyname.insurance</groupId>
<artifactId>health</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<name>health</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>
</project>
App.java
Maven 会自动生成一个测试的 java 文件 App.java。
路径:**/workspace/java/health/src/main/java/com/companyname/insurance**
package com.companyname.insurance;
/**
* Hello world!
*
*/
public class App
{
public static void main( String[] args )
{
System.out.println( "Hello World!" );
}
}
AppTest.java
Maven 会自动生成一个 java 文件 AppTest.java。
路径为: /workspace/java/health/src/main/java/com/companyname/insurance
package com.companyname.insurance;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
/**
* Unit test for simple App.
*/
public class AppTest
extends TestCase
{
/**
* Create the test case
*
* @param testName name of the test case
*/
public AppTest( String testName )
{
super( testName );
}
/**
* @return the suite of tests being tested
*/
public static Test suite()
{
return new TestSuite( AppTest.class );
}
/**
* Rigourous Test :-)
*/
public void testApp()
{
assertTrue( true );
}
}
就这样。现在你可以看到 Maven 的强大之处。你可以用 maven 简单的命令创建任何类型的项目,并且可以启动我们的开发。