Maven 3 warnings about build.plugins.plugin.version

Solution 1:

Add a <version> element after the <plugin> <artifactId> in your pom.xml file. Find the following text:

<plugin>
  <artifactId>maven-compiler-plugin</artifactId>

Add the version tag to it:

<plugin>
  <artifactId>maven-compiler-plugin</artifactId>
  <version>2.3.2</version>

The warning should be resolved.

Regarding this:

'build.plugins.plugin.version' for org.apache.maven.plugins:maven-compiler-plugin is missing

Many people have mentioned why the issue is happening, but fail to suggest a fix. All I needed to do was to go into my POM file for my project, and add the <version> tag as shown above.

To discover the version number, one way is to look in Maven's output after it finishes running. Where you are missing version numbers, Maven will display its default version:

[INFO] --- maven-compiler-plugin:2.3.2:compile (default-compile) @ entities ---

Take that version number (as in the 2.3.2 above) and add it to your POM, as shown.

Solution 2:

Run like:

  $ mvn help:describe -DartifactId=maven-war-plugin -DgroupId=org.apache.maven.plugins

for plug-in that have no version. You get output:

Name: Maven WAR Plugin
Description: Builds a Web Application Archive (WAR) file from the project
  output and its dependencies.
Group Id: org.apache.maven.plugins
Artifact Id: maven-war-plugin
Version: 2.2
Goal Prefix: war

Use version that shown in output.

UPDATE If you want to select among list of versions, use http://search.maven.org/ or http://mvnrepository.com/ Note that your favorite Java IDE must have Maven package search dialog. Just check docs.

SUPER UPDATE I also use:

$ mvn dependency:tree
$ mvn dependency:list
$ mvn dependency:resolve
$ mvn dependency:resolve-plugins  # <-- THIS

Recently I discover how to get latest version for plug-in (or library) so no longer needs for googling or visiting Maven Central:

$ mvn versions:display-dependency-updates
$ mvn versions:display-plugin-updates     # <-- THIS

Solution 3:

Maven 3 is more restrictive with the POM-Structure. You have to set versions of Plugins for instance.

With maven 3.1 these warnings may break you build. There are more changes between maven2 and maven3: https://cwiki.apache.org/confluence/display/MAVEN/Maven+3.x+Compatibility+Notes

Solution 4:

get the latest version information from:

https://mvnrepository.com/artifact/org.apache.maven.plugins/maven-compiler-plugin

click on the latest version (or the one you'd like to use) and you'll see the the dependency info (as of 2019-05 it's 3.8.1):

<!-- https://mvnrepository.com/artifact/org.apache.maven.plugins/maven-compiler-plugin -->
<dependency>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-compiler-plugin</artifactId>
  <version>3.8.1</version>
</dependency>

you might want to use the version tag and the comment for your plugin tag.

<!-- https://mvnrepository.com/artifact/org.apache.maven.plugins/maven-compiler-plugin -->
<plugin>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.8.1</version>
    <configuration>
        <source />
        <target />
    </configuration>
</plugin>

if you like you can modify your pom to have the version information in the properties tag as outlined in another answer.