十二、Maven 工程模版

Maven – 工程模板

Maven 使用原型(Archetype)概念为用户提供了大量不同类型的工程模版(614 个)。Maven 使用下面的命令帮助用户快速创建 java 项目。

mvn archetype:generate

什么是原型?

原型是一个 Maven 插件,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。

使用工程模板

让我们打开命令控制台,跳转到 C:\ > MVN 目录并执行以下 mvn 命令

C:\MVN>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
...
600: remote -> org.trailsframework:trails-archetype (-)
601: remote -> org.trailsframework:trails-secure-archetype (-)
602: remote -> org.tynamo:tynamo-archetype (-)
603: remote -> org.wicketstuff.scala:wicket-scala-archetype (-)
604: remote -> org.wicketstuff.scala:wicketstuff-scala-archetype 
Basic setup for a project that combines Scala and Wicket,
depending on the Wicket-Scala project. 
Includes an example Specs test.)
605: remote -> org.wikbook:wikbook.archetype (-)
606: remote -> org.xaloon.archetype:xaloon-archetype-wicket-jpa-glassfish (-)
607: remote -> org.xaloon.archetype:xaloon-archetype-wicket-jpa-spring (-)
608: remote -> org.xwiki.commons:xwiki-commons-component-archetype 
(Make it easy to create a maven project for creating XWiki Components.)
609: remote -> org.xwiki.rendering:xwiki-rendering-archetype-macro 
(Make it easy to create a maven project for creating XWiki Rendering Macros.)
610: remote -> org.zkoss:zk-archetype-component (The ZK Component archetype)
611: remote -> org.zkoss:zk-archetype-webapp (The ZK wepapp archetype)
612: remote -> ru.circumflex:circumflex-archetype (-)
613: remote -> se.vgregion.javg.maven.archetypes:javg-minimal-archetype (-)
614: remote -> sk.seges.sesam:sesam-annotation-archetype (-)
Choose a number or apply filter 
(format: [groupId:]artifactId, case sensitive contains): 203:

按下Enter 选择默认选项 (203:maven-archetype-quickstart)

Maven 将询问原型的版本

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
Choose a number: 6:

按下Enter 选择默认选项 (6:maven-archetype-quickstart:1.1)

Maven 将询问工程细节。按要求输入工程细节。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 将要求确认工程细节。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 将开始创建工程结构,显示如下:

[INFO] -----------------------------------------------------------------------
[INFO] Using following parameters for creating project 
from Old (1.x) Archetype: maven-archetype-quickstart:1.1
[INFO] -----------------------------------------------------------------------
[INFO] Parameter: groupId, Value: com.companyname.insurance
[INFO] Parameter: packageName, Value: com.companyname.insurance
[INFO] Parameter: package, Value: com.companyname.insurance
[INFO] Parameter: artifactId, Value: health
[INFO] Parameter: basedir, Value: C:\MVN
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] project created from Old (1.x) Archetype in dir: C:\MVN\health
[INFO] -----------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
[INFO] -----------------------------------------------------------------------
[INFO] Total time: 4 minutes 12 seconds
[INFO] Finished at: Fri Jul 13 11:10:12 IST 2012
[INFO] Final Memory: 20M/90M
[INFO] -----------------------------------------------------------------------

创建的项目

现在转到 C:\ > MVN 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工程,如下所示:

 

创建 POM.xml

Maven 为工程生成一个 POM.xml文件,如下所列:

<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>

创建 App.java

Maven 生成一个 java 源文件示例,工程的 App.java 如下所示:

路径:C:\ > MVN > health > src > main > java > com > companyname > insurance > App.java

package com.companyname.insurance;
/**
* Hello world!
*/
public class App 
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );
    }

创建 AppTest.java

Maven 生成一个 java 源文件示例,工程的 AppTest.java 如下所示:

路径为: C:\ > MVN > health > src > test > java > com > companyname > insurance > AppTest.java

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工程,并且可以启动您的开发。