<?xml version="1.0" encoding="UTF-8"?>
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<!-- START SNIPPET: superpom -->
<project>
<modelVersion>4.0.0</modelVersion>
<repositories>
<repository>
<id>central</id>
<name>Central Repository</name>
<url>https://repo.maven.apache.org/maven2</url>
<layout>default</layout>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>central</id>
<name>Central Repository</name>
<url>https://repo.maven.apache.org/maven2</url>
<layout>default</layout>
<snapshots>
<enabled>false</enabled>
</snapshots>
<releases>
<updatePolicy>never</updatePolicy>
</releases>
</pluginRepository>
</pluginRepositories>
<build>
<directory>${project.basedir}/target</directory>
<outputDirectory>${project.build.directory}/classes</outputDirectory>
<finalName>${project.artifactId}-${project.version}</finalName>
<testOutputDirectory>${project.build.directory}/test-classes</testOutputDirectory>
<sourceDirectory>${project.basedir}/src/main/java</sourceDirectory>
<scriptSourceDirectory>${project.basedir}/src/main/scripts</scriptSourceDirectory>
<testSourceDirectory>${project.basedir}/src/test/java</testSourceDirectory>
<resources>
<resource>
<directory>${project.basedir}/src/main/resources</directory>
</resource>
</resources>
<testResources>
<testResource>
<directory>${project.basedir}/src/test/resources</directory>
</testResource>
</testResources>
<pluginManagement>
<!-- NOTE: These plugins will be removed from future versions of the super POM -->
<!-- They are kept for the moment as they are very unlikely to conflict with lifecycle mappings (MNG-4453) -->
<plugins>
<plugin>
<artifactId>maven-antrun-plugin</artifactId>
<version>1.3</version>
</plugin>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>2.2-beta-5</version>
</plugin>
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.8</version>
</plugin>
<plugin>
<artifactId>maven-release-plugin</artifactId>
<version>2.3.2</version>
</plugin>
</plugins>
</pluginManagement>
</build>
<reporting>
<outputDirectory>${project.build.directory}/site</outputDirectory>
</reporting>
<profiles>
<!-- NOTE: The release profile will be removed from future versions of the super POM -->
<profile>
<id>release-profile</id>
<activation>
<property>
<name>performRelease</name>
<value>true</value>
</property>
</activation>
<build>
<plugins>
<plugin>
<inherited>true</inherited>
<artifactId>maven-source-plugin</artifactId>
<executions>
<execution>
<id>attach-sources</id>
<goals>
<goal>jar</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<inherited>true</inherited>
<artifactId>maven-javadoc-plugin</artifactId>
<executions>
<execution>
<id>attach-javadocs</id>
<goals>
<goal>jar</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<inherited>true</inherited>
<artifactId>maven-deploy-plugin</artifactId>
<configuration>
<updateReleaseInfo>true</updateReleaseInfo>
</configuration>
</plugin>
</plugins>
</build>
</profile>
</profiles>
</project>
<!-- END SNIPPET: superpom -->
2.解读
- 仓库配置
<repositories>
<repository>
<id>central</id>
<name>Central Repository</name>
<url>https://repo.maven.apache.org/maven2</url>
<layout>default</layout>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>central</id>
<name>Central Repository</name>
<url>https://repo.maven.apache.org/maven2</url>
<layout>default</layout>
<snapshots>
<enabled>false</enabled>
</snapshots>
<releases>
<updatePolicy>never</updatePolicy>
</releases>
</pluginRepository>
</pluginRepositories>
表明：依赖仓库支持发布版本依赖下载，更新策略默认为每天检查一次，不支持快版下载。
插件仓库发布版本依赖下载，更新策略为从不更新（意味着所有插件都要指定版本号，并且不会更新），不支持快照版本下载。疑问？
超级POM中为什么没有指定default周期中默认插件的版本信息？还是我没找到？因为如果没指定会正常根据更新策略解析发布版本构件，而由上面可知，发布版本的更新策略为“从不更新”。
看其中一段,声明了对插件maven-antrun-plugin的依赖
<plugin>
<artifactId>maven-antrun-plugin</artifactId>
<version>1.3</version>
</plugin>
进入本地仓库查看发现有两个版本1.3和1.8
Paste_Image.png
1.3版本内容如下：说明处于更新状态，还没从远程仓库下载到。
maven-antrun-plugin-1.3构件处于更新状态
1.8版本内容如下：完整的插件
maven-antrun-plugin-1.8
maven-antrun-plugin-1.3.jar.lastUpdated中内容：
#NOTE: This is an Aether internal implementation file, its format can be changed without prior notice.
#Sun Dec 11 16:28:41 CST 2016
http\://172.19.201.155\:8081/repository/maven-public/.lastUpdated=1481444921950
http\://172.19.201.155\:8081/repository/maven-public/.error=
说明下载1.3版本失败。通过地址访问私服也没有查看到相应构件。
更新构件失败，因为在nexus上没找到该构件
在nexus私服中搜索也只发现有1.8版本的插件
maven-antrun-plugin在远程仓库Nexus上的版本
