Using the Maven Injection Plugin

1. Add the plugin to your Maven build
2. Configure injections

   For usage details see the inject goal description.

   Hint: Inject into accessor methods instead of class attributes or constants to avoid surprises (compiler inlining etc.) Hint: A typical singleton could use a Java Enum, see BuildInfo example.

3. Hook plugin into lifecycle after compilation

   The plugin runs after compilation in the *process-classes* phase.

4. Add build info plugin for injecting the SCM version and branch, as an example

   <build>
     ...
     <plugins>
       <plugin>
         <groupId>de.m3y.maven</groupId> <!-- (1) Add the plugin to your Maven build -->
         <artifactId>inject-maven-plugin</artifactId>
         <version>1.7</version>
         <configuration> <!-- (2) Configure injections -->
           <injections>
             <injection>
               <value>1.7</value> <!-- Inject Maven project version -->
               <pointCuts>
                 <pointCut>de.m3y.maven.inject.it.ExampleInjection.getVersion</pointCut> <!-- ... into accessor -->
                 <pointCut>...</pointCut> <!-- Could do multi injection -->
               </pointCuts>
             </injection>
             <injection>
               <value>${maven.build.timestamp}</value>
               <pointCut>de.m3y.maven.inject.it.ExampleInjection.getBuildTimeStamp</pointCut>
             </injection>
             <injection>
               <value>${buildNumber}</value> <!-- Provided by buildnumber-maven-plugin -->
               <pointCut>de.m3y.maven.inject.it.ExampleInjection.getScmVersion</pointCut>
             </injection>
             <injection>
               <value>${scmBranch}</value> <!-- Provided by buildnumber-maven-plugin -->
               <pointCut>de.m3y.maven.inject.it.ExampleInjection.getScmBranch</pointCut>
             </injection>
           </injections>
         </configuration>
         <executions>
           <execution> <!-- (3) Hook plugin into lifecycle after compilation-->
             <phase>process-classes</phase>
             <goals>
               <goal>inject</goal>
             </goals>
           </execution>
         </executions>
       </plugin>
       <plugin> <!-- (4) Required for SCM properties buildNumber and scmBranch
                         See https://github.com/mojohaus/mojo-parent -->
         <groupId>org.codehaus.mojo</groupId>
         <artifactId>buildnumber-maven-plugin</artifactId>
         <version>1.4</version>
         <executions>
           <execution>
             <phase>validate</phase>
             <goals>
               <goal>create</goal>
             </goals>
           </execution>
         </executions>
         <configuration>
           <doCheck>false</doCheck>
           <doUpdate>false</doUpdate>
         </configuration>
       </plugin>
     </plugins>
     ...
   </build>