MAVEN_USER_HOME="${MAVEN_USER_HOME:-${HOME}/.m2}"
MAVEN_HOME="${MAVEN_USER_HOME}/wrapper/dists/${distributionUrlNameMain-}/$(hash_string "$distributionUrl")"

exec_maven() {
  unset MVNW_VERBOSE MVNW_USERNAME MVNW_PASSWORD MVNW_REPOURL || :
  exec "$MAVEN_HOME/bin/$MVN_CMD" "$@" || die "cannot exec $MAVEN_HOME/bin/$MVN_CMD"
}

if [ -d "$MAVEN_HOME" ]; then
  verbose "found existing MAVEN_HOME at $MAVEN_HOME"
  exec_maven "$@"
fi

 */
public final class Constants {

    /**
     * Maven home.
     *
     * @since 3.0.0
     */
    @Config(readOnly = true, source = Config.Source.SYSTEM_PROPERTIES)
    public static final String MAVEN_HOME = "maven.home";

    /**
     * Maven version.
     *
     * @since 3.0.0
     */
    @Config(readOnly = true, source = Config.Source.SYSTEM_PROPERTIES)