Maven 3 warnings about build.plugins.plugin.version

Question

Since I updated to Maven 3 I get the following warning messages at each build :

How can I get rid of these warnings?

[INFO] Scanning for projects...
[WARNING] 
[WARNING] Some problems were encountered while building the effective model for proj:id:jar:3.1
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-javadoc-plugin is missing. @ line 195, column 15
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-compiler-plugin is missing. @ line 204, column 15
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-surefire-plugin is missing. @ line 227, column 15
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-jar-plugin is missing. @ line 215, column 15
[WARNING] 'reporting.plugins.plugin.version' for org.codehaus.mojo:jdepend-maven-plugin is missing. @ line 271, column 15
[WARNING] 
[WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
[WARNING] 
[WARNING] For this reason, future Maven versions might no longer support building such malformed projects.

Answer 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.