mvn依赖版本控制dependencyManagement

mvn 依赖仓库管理脚本. 其中有一些简化的方式.

什么是父子项目

• 在目录结构上一般体现为parent为外层,child为内层.用idea创建一个mvn项目,New->Module… 创建一个mvn子项目(groupId必须一致).

• pom.xml文件的特征为:

  //parent 添加 module
  <modules>
      <module>son-one</module>
  </modules>
  //child 添加 parent
  <parent>
      <artifactId>abc</artifactId>
      <groupId>com.example</groupId>
      <version>1.0-SNAPSHOT</version>
      <!-- <relativePath>../pom.xml</relativePath> -->
  </parent>
  

子项目自动获取parent 项目依赖

parent项目添加依赖

    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>${mybatis-version}</version>
        </dependency>
    </dependencies>

child项目编写测试代码

package com.example.son1;

import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class Main {
   public static void main(String[] args) {
       System.out.println("Hello world!");
       SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
   }
}

编译通过.

如果将 parent mybatis dependency注释掉,SqlSessionFactoryBuilder就找不到了.

父子项目 通过 dependencyManagement 进行版本的统一管理.

dependencyManagement简化child(包括同级)项目版本配置

• parent project 设置 dependencyManagement

 <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>${mybatis-version}</version>
            </dependency>

            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>${mysql-connector-version}</version>
            </dependency>

            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>${junit-version}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>

• child project 省略版本设置

    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
        </dependency>
    </dependencies>

如果将dependencyManagement注释掉,

Could not find artifact org.mybatis:mybatis:pom:unknown in aliyun (https://maven.aliyun.com/repository/public)

当然, 如果child project使用的version和dependencyManagement不一致需要进行单独设置.

组导入

正常情况下: 要求child project dependency groupId&&artifactId与 dependencyManagement下定义的一致,为了便于处理,可以进行组导入.

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2021.0.5.0</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

导入nacos配置启动器时,并不需要version.

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>

然后 https://central.sonatype.com/ 查看了type指定要导入的类型jar
war\pom. pom就是导入一组配置.

<project
    ...
    <dependencyManagement>
    <dependencies>
    <dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
    <version>2021.0.5.0</version>
    </dependency>
...

spring-cloud-alibaba-dependencies-2021.0.5.0.pom

当然就不需要在写version.

完整代码

• parent project pom.xml

<?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.example</groupId>
    <artifactId>abc</artifactId>
    <packaging>pom</packaging>
    <version>1.0-SNAPSHOT</version>
    <modules>
        <module>son-one</module>
    </modules>

    <properties>
        <mybatis-version>3.5.9</mybatis-version>
        <mysql-connector-version>8.0.33</mysql-connector-version>
        <junit-version>4.13.2</junit-version>
    </properties>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>${mybatis-version}</version>
            </dependency>

            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>${mysql-connector-version}</version>
            </dependency>

            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>${junit-version}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>


    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
        </dependency>
    </dependencies>

</project>

• child project pom.xml

<?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">
    <parent>
        <artifactId>abc</artifactId>
        <groupId>com.example</groupId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../pom.xml</relativePath>
    </parent>

    <modelVersion>4.0.0</modelVersion>

    <artifactId>son-one</artifactId>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
        </dependency>
    </dependencies>


</project>

参考内容 Maven创建父子工程详解