protected void start() {
            if (start == null) {
                start = MonotonicClock.now();
                resumed = start;
            } else {
                resumed = MonotonicClock.now();
            }
        }

        protected void stop() {
            end = MonotonicClock.now();
            exec = exec.plus(Duration.between(resumed, end));
        }

import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.function.Function;
import java.util.stream.Stream;

import org.apache.maven.api.MonotonicClock;
import org.apache.maven.api.Session;
import org.apache.maven.api.model.Model;
import org.apache.maven.api.model.Prerequisites;
import org.apache.maven.api.model.Profile;
import org.apache.maven.api.services.Lookup;