This plugin can build a subset of interdependent projects in a reactor. It should be useful in large reactor builds that include irrelevant stuff you're not working on.
The Reactor plugin has several goals:
Example: mvn reactor:resume -Dfrom=bar
Example: mvn reactor:make -Dmake.folders=foo,bar
Example: mvn reactor:make-dependents -Dmake.folders=foo,bar
Example: mvn reactor:make-scm-changes
The goals reactor:make and reactor:make-dependents are very similar. They differ in the direction of dependency analysis.
For example, suppose project "fooUI" depends on project "barBusinessLogic", which depends on project "bazDataAccess".
fooUI --> barBusinessLogic --> bazDataAccess
Ordinarily, when building, you'll first build bazDataAccess, then barBusinessLogic, then fooUI.
barBusinessLogic --> bazDataAccess
fooUI --> barBusinessLogic
In other words, reactor:make walks *down* the dependency tree, whereas reactor:make-dependents walks *up* the dependency tree.
To provide you with better understanding on some usages of the Reactor Plugin, you can take a look at the examples page.