pom将依赖切换成国内镜像教程 pom依赖多个版本

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mob64ca14068b0b 2024-06-03 12:56:55

文章标签 pom将依赖切换成国内镜像教程 maven spring xml 文章分类 云原生云计算

今天，我们来了解下如何管理和优化父项目和子模块的依赖包版本，又或者我们希望子项目B不需要全部依赖父项目A的内容，避免一股脑全部导入。

首先，来看四个pom文件：

1、demo-parent

<?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.demo</groupId>
	<artifactId>demo-parent</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>pom</packaging>

	<name>demo-parent</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.0.5.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>

	<modules>
		<module>demo-apply</module>
		<module>demo-common</module>
		<module>demo-static</module>
	</modules>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.1</version>
				<configuration>
					<source>${java.version}</source>
					<target>${java.version}</target>
				</configuration>
			</plugin>
		</plugins>
	</build>

</project>

2、demo-apply

<?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>

    <artifactId>demo-apply</artifactId>
    <packaging>jar</packaging>

    <name>demo-apply</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>com.demo</groupId>
        <artifactId>demo-parent</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <relativePath>../pom.xml</relativePath><!-- lookup parent from repository -->
    </parent>

    <dependencies>
        <!-- 加入其余模块的依赖 -->
        <dependency>
            <groupId>com.demo</groupId>
            <artifactId>demo-common</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>com.demo</groupId>
            <artifactId>demo-static</artifactId>
            <version>0.0.1-SNAPSHOT</version>
            <type>war</type>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <!-- 当所依赖的其他模块，有启动类的时候，需要以下配置，指定唯一启动类，
                        本次事例未涉及其他模块有启动类，可自行测试 -->
                <configuration>
                    <!-- 指定该Main Class为全局的唯一入口 -->
                    <mainClass>com.demo.demoapply.DemoApplyApplication</mainClass>
                    <layout>ZIP</layout>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>repackage</goal><!--可以把依赖的包都打包到生成的Jar包中-->
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

</project>

3、demo-static

<?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>

	<artifactId>demo-static</artifactId>
	<packaging>war</packaging>

	<name>demo-static</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>com.demo</groupId>
		<artifactId>demo-parent</artifactId>
		<version>0.0.1-SNAPSHOT</version>
		<relativePath>../pom.xml</relativePath><!-- lookup parent from repository -->
	</parent>

	<dependencies>

	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.1</version>
				<configuration>
					<source>${java.version}</source>
					<target>${java.version}</target>
				</configuration>
			</plugin>
		</plugins>
	</build>


</project>

4、demo-common

<?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>

	<artifactId>demo-common</artifactId>
	<packaging>jar</packaging>

	<name>demo-common</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>com.demo</groupId>
		<artifactId>demo-parent</artifactId>
		<version>0.0.1-SNAPSHOT</version>
		<relativePath>../pom.xml</relativePath><!-- lookup parent from repository -->
	</parent>

	<dependencies>

	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.1</version>
				<configuration>
					<source>${java.version}</source>
					<target>${java.version}</target>
				</configuration>
			</plugin>
		</plugins>
	</build>


</project>

很明显，我们的demo-parent为父项目，demo-apply为应用入口，demo-common放的应该是共用工具类，demo-static应该是共用的静态文件，如页面等，demo-apply依赖两者。

好，看到这里，就有疑问了，按理来说，demo-static，存放页面，打包成war包，应该不需要可以运行，那么也就不需要依赖springboot的包，那么我们进行如下改变：

demo-parent:

<?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.demo</groupId>
    <artifactId>demo-parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

    <name>demo-parent</name>
    <description>Demo project for Spring Boot</description>

    <!-- 删除 -->
    <!--<parent>-->
        <!--<groupId>org.springframework.boot</groupId>-->
        <!--<artifactId>spring-boot-starter-parent</artifactId>-->
        <!--<version>2.0.5.RELEASE</version>-->
        <!--<relativePath/> <!– lookup parent from repository –>-->
    <!--</parent>-->

    <modules>
        <module>demo-apply</module>
        <module>demo-common</module>
        <module>demo-static</module>
    </modules>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
                <version>2.0.5.RELEASE</version>
            </dependency>

            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
                <version>2.0.5.RELEASE</version>
            </dependency>

            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <version>2.0.5.RELEASE</version>
                <scope>test</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

demo-apply

<?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>

    <artifactId>demo-apply</artifactId>
    <packaging>jar</packaging>

    <name>demo-apply</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>com.demo</groupId>
        <artifactId>demo-parent</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <relativePath>../pom.xml</relativePath><!-- lookup parent from repository -->
    </parent>

    <dependencies>
        <!-- 加入其余模块的依赖 -->
        <dependency>
            <groupId>com.demo</groupId>
            <artifactId>demo-common</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>com.demo</groupId>
            <artifactId>demo-static</artifactId>
            <version>0.0.1-SNAPSHOT</version>
            <type>war</type>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <!-- 当所依赖的其他模块，有启动类的时候，需要以下配置，指定唯一启动类，
                        本次事例未涉及其他模块有启动类，可自行测试 -->
                <configuration>
                    <!-- 指定该Main Class为全局的唯一入口 -->
                    <mainClass>com.demo.demoapply.DemoApplyApplication</mainClass>
                    <layout>ZIP</layout>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>repackage</goal><!--可以把依赖的包都打包到生成的Jar包中-->
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

</project>

大功告成，虽然这样是OK了，大家查看依赖发现也对，demo-static和demo-common，已经不依赖springBoot，但是有心人一定会问，demo-parent为何删除这一段：

<!-- 删除 -->
    <!--<parent>-->
        <!--<groupId>org.springframework.boot</groupId>-->
        <!--<artifactId>spring-boot-starter-parent</artifactId>-->
        <!--<version>2.0.5.RELEASE</version>-->
        <!--<relativePath/> <!– lookup parent from repository –>-->
    <!--</parent>-->

首先，告诉大家这一段从哪里来的，idea在生成springBoot项目的时候，会采取官方建议，默认引入该父项目。

那么问题又来了，这个父项目到底是个啥，我们默认要引入他，大家可以点击进去查看，其实他只是个pom文件，管理了一些默认的配置信息，这样才能做到，我们在默认生成项目的时候，发现我们的dependency中不需要引入版本，应为他会集成父Pom文件的版本信息。

<dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
            </dependency>
            
       	    ...
       	    
        </dependencies>
    </dependencyManagement>

既然知道，原来是这么回事，那我们顺便查下SpringBoot的官网介绍吧，是否还有更好的方式。

果真，还有一种方式：

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-dependencies</artifactId>
            <version>1.5.1.RELEASE</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

请注意，它的 type 是 pom，scope 是 import，这种类型的 dependency 只能在 dependencyManagement 标签中声明。

同样我们在点进去看，原来这个POM文件已经默认给我们使用dependencyManagement声明了很多依赖，我们如果需要直接在我们的dependency中加入依赖就行，而无需指定版本。
这样demo-parent的Pom文件就变成了这个样子：

<?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.demo</groupId>
    <artifactId>demo-parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

    <name>demo-parent</name>
    <description>Demo project for Spring Boot</description>

    <modules>
        <module>demo-apply</module>
        <module>demo-common</module>
        <module>demo-static</module>
    </modules>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>2.0.0.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

这样parent项目的POM依赖就会特别清晰。

注释：dependencyManagement 包裹的dependencies只有声明作用，不会实际导入，另外关于maven中的继承、聚合等多多了解，就能很好的理解上述的内容。

源码：https://github.com/ATSJP/Study-Springboot-Demo.git，
请切换为DV_2018_10_15分支查看。

好的东西都在这里>>> 官网：Spring官网

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