code: public void execute(AbstractWisdomMojo mojo) throws MojoExecutionException {
          String version = PluginExtractor.getBuildPluginVersion(mojo, MAVEN_COMPILER_PLUGIN);
          if (version == null) {
              version = DEFAULT_VERSION;
          }
          final Plugin plugin = plugin(
                  GROUP_ID,
                  MAVEN_COMPILER_PLUGIN,
                  version
          );
  
          Xpp3Dom configuration = PluginExtractor.getBuildPluginConfiguration(mojo, MAVEN_COMPILER_PLUGIN, COMPILE_GOAL);
          if (configuration == null) {
              Properties properties = mojo.project.getProperties();
              String source = properties.getProperty("maven.compiler.source", "1.7");
              String target = properties.getProperty("maven.compiler.target", "1.7");
              configuration = configuration(
                      element("compileSourceRoots", "${project.compileSourceRoots}"),
                      element("classpathElements", "${project.compileClasspathElements}"),
                      element("outputDirectory", "${project.build.outputDirectory}"),
                      element("projectArtifact", "${project.artifact}"),
                      element("generatedSourcesDirectory",
                              "${project.build.directory}/generated-sources/annotations"),
                      element("target", source),
                      element("source", target)
              );
          } else {
              mojo.getLog().debug("Loading maven-compiler-plugin configuration:");
              PluginExtractor.extractEligibleConfigurationForGoal(mojo, plugin, COMPILE_GOAL, configuration);
              mojo.getLog().debug(configuration.toString());
  
          }
  
          // Compile sources
          executeMojo(
                  plugin,
                  goal(COMPILE_GOAL),
                  configuration,
                  executionEnvironment(
                          mojo.project,
                          mojo.session,
                          mojo.pluginManager
                  )
          );
      }
docs: Compiles java classes from 'src/main/java'.
  
  @param mojo the mojo
  @throws MojoExecutionException if the compilation fails.