使用场景：

maven打出的jar中pom.xml动态替换占位符
有些时候某些公共工具jar包被项目引用后发现公共jar的pom.xml中的version依然还是占位符，例如下面

        <dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>${lombok.version}</version></dependency>

如何让其打包后动态替换呢，即替换为最终的版本,像下面这样

        <dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>>1.18.8</version></dependency>

打包后发现会在jar包中生成如果路径:target/classes/META-INF/maven/$groupId/${artifactId}/pom.xml,经测试这个pom.xml才是最终生效的配置,那么如何替换呢。经过查找maven源码发现是硬编码到jar中的,源码如下
org.apache.maven.archiver.MavenArchiver#createArchive

所以我这边采取的是通过copy-resources重新替换解析后pom到META-INF/maven/$groupId/${artifactId}/pom.xml,解决方法如下:

<dependencies>......
</dependencies>
<build><plugins><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-resources-plugin</artifactId><executions><execution><!--不要定义为default-resources，否则会覆盖maven默认的--><id>default-resources1</id><phase>validate</phase><goals><goal>copy-resources</goal></goals><configuration><!--将当前项目下pom.xml解析替换占位符复制到目标文件中--><outputDirectory>target/classes/META-INF/maven/${groupId}/${artifactId}/</outputDirectory><overwrite>true</overwrite><resources><resource><directory>./</directory><includes><include>pom.xml</include></includes><filtering>true</filtering></resource></resources></configuration></execution></executions></plugin><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-plugin-plugin</artifactId><version>3.5</version><configuration><skipErrorNoDescriptorsFound>true</skipErrorNoDescriptorsFound></configuration></plugin><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-jar-plugin</artifactId><version>3.2.0</version><executions><execution><phase>generate-resources</phase><goals><goal>jar</goal></goals></execution></executions></plugin></plugins></build>

另外maven如何错误的类不打入包内

因为依赖的环境不同,有些类可能会出现编译错误不想打入jar中，可以通过在profile中自定义插件排除,如下:在saas_prod打包时所有com/xxx/local 包下面的类将不会打入其中

    <profile><id>saas_prod</id><activation><activeByDefault>true</activeByDefault></activation><build><plugins><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><version>3.8.1</version><configuration><excludes><exclude>com/xxx/local/**/*.java</exclude></excludes></configuration></plugin></plugins></build></profile>