We use a number of third-party libraries to build our projects. As you recall, we specify the groupId, artifactId, and version elements of each of these dependant libraries in our pom file. There may be many occasions when there are updates to these libraries and new versions are released. It will be good to have a mechanism to get notified about these releases and update the project build file suitably.
- Take a project for which you want to check for a dependency update,
simple-project, which we had created using the quick-start archetype. - Run the following command:
mvn versions:display-dependency-updates - Observe the output:
[INFO] --- versions-maven-plugin:2.1:display-dependency-updates (default-cli) @ simple-project --- [INFO] artifact junit:junit: checking for updates from central [INFO] The following dependencies in Dependencies have newer versions: [INFO] junit:junit ............................................ 3.8.1 -> 4.12
The display-dependency-updates goal of the Maven Versions plugin uses the metadata of each of the maven dependencies to determine the latest version of each dependency. If it does not match the current version, it displays a report about the difference.
We have already seen earlier that SNAPSHOT versions are handled differently by Maven, and it automatically checks and updates these dependencies for each build as per the configuration. If the version number of the SNAPSHOT changes (1.0-SNAPSHOT to 1.1-SNAPSHOT), then the Versions plugin indicates that.