Linux中用maven创建一个简单的项目

maven简介

maven是Apache旗下的管理java项目jar包的项目管理工具，有了它可以很方便的构建管理java项目。

安装maven

maven下载地址
http://maven.apache.org/download.cgi
下载合适的版本

将maven解压至/usr/local目录下

[root@localhost local]# tar -zxvf apache-maven-3.3.9-bin.tar.gz

添加环境变量

[root@localhost local]# vim /etc/profile
export MAVEN_HOME=/usr/local/apache-maven-3.3.9
export PATH=$MAVEN_HOME/bin:$PATH[root@localhost local]# mvn -v
Apache Maven 3.3.9 (bb52d8502b132ec0a5a3f4c09453c07478323dc5; 2015-11-11T00:41:47+08:00)
Maven home: /usr/local/apache-maven-3.3.9
Java version: 1.8.0_171, vendor: Oracle Corporation
Java home: /usr/local/jdk1.8.0_171/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "3.10.0-229.el7.x86_64", arch: "amd64", family: "unix"

创建maven项目文件

[root@localhost apache-maven-3.3.9]# mvn archetype:generate

执行命令后会自动联网下载一些插件，然后要求选择项目类型，我选择了默认，然后按要求输入信息会创建一个maven工程样例

进入创建的maven项目，用tree命令查看创建的项目结构，没有tree就yum install一个

[root@localhost apache-maven-3.3.9]# cd maven-project/
[root@localhost maven-project]# tree
bash: tree: command not found…
[root@localhost maven-project]# yum install tree -y[root@localhost maven-project]# tree
.
├── pom.xml
└── src
├── main
│ └── java
│ └── maven-test
│ └── App.java
└── test
└── java
└── maven-test
└── AppTest.java7 directories, 3 files

maven项目文件说明

上图可以看出maven项目结构，由pom.xml和src目录组成，src下面为main和test，pom.xml是maven项目管理文件，可以向该文件添加打包，编译插件。main目录存放项目源码，test文件存放代码。

[root@localhost maven-project]# cat pom.xml

<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>maven</groupId><artifactId>maven-project</artifactId><version>1</version><packaging>jar</packaging><name>maven-project</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>

上面的pom.xml是自动生成的，详细说明如下：
<groupId>:创建项目时指定groupId
<artifactld>:创建项目时指定的artifactId
<version>:创建项目时指定的version
<packaging>:项目编译后，打成jar包发布
<denpendency>:测试时需要的jar包。

main目录

main目录存放java源文件，如创建的模板文件App.java

[root@localhost maven-project]# cat src/main/java/maven-test/App.java

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

test目录
test目录存放源代码的测试文档，如创建的模板文件的AppTest.java

[root@localhost maven-project]# cat src/test/java/maven-test/AppTest.java

package maven-test;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 );}
}

上传maven项目至gitlab

进入maven项目所在目录
输入git config --global user.name “你的gitlab用户名”
输入git config --global user.email “你的gitlab的邮箱”
输入git init
输入git remote add orgin 你的gitlab的项目地址
输入git add .
输入git commit
输入git push -u origin master 将maven项目推送到gitlab端

[root@localhost maven-project]# git push -u origin master
Username for 'https://gitlab.com': *************@qq.com
Password for 'https://*******************@qq.com@gitlab.com':
Counting objects: 13, done.
Compressing objects: 100% (6/6), done.
Writing objects: 100% (13/13), 1.40 KiB | 0 bytes/s, done.
Total 13 (delta 0), reused 0 (delta 0)
To https://gitlab.com/lucky123dog/test.gitad9d1fc..e63f521  master -> master
Branch master set up to track remote branch master from origin.

刷新gitlab页面，已经可以看到刚才从远端推送的maven项目了

将默认生成的maven项目打包部署到tomcat

默认maven项目会生成pom.xml文件和src目录

[root@localhost maven-project]# ls
pom.xml  src

打包

[root@localhost maven-project]# mvn clean
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building maven-project 1
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ maven-project ---
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.233 s
[INFO] Finished at: 2020-03-31T16:31:52+08:00
[INFO] Final Memory: 6M/29M
[INFO] ------------------------------------------------------------------------

[root@localhost maven-project]# mvn install
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building maven-project 1
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 11.747 s
[INFO] Finished at: 2020-03-31T16:32:50+08:00
[INFO] Final Memory: 14M/35M
[INFO] ------------------------------------------------------------------------

生成一个target目录，里面有刚才打包的项目

[root@localhost maven-project]# ls
pom.xml  src  target
[root@localhost maven-project]# cd target/
[root@localhost target]# ls
classes  maven-archiver  maven-project-1.jar  maven-status  surefire-reports  test-classes

将刚才打好的jar包复制到tomcat/webapps/目录下

[root@localhost target]# cp maven-project-1.jar /usr/local/tomcat/webapps/

运行
[root@localhost webapps]# java -jar maven-project-1.jar
Hello World!