private final Map<MavenProject, List<MavenProject>> projects;
    private final Map<String, String> aliases = new HashMap<>();
    private volatile Set<String> duplicateIds;
    private volatile List<BuildStep> sortedNodes;

    BuildPlan() {
        this.projects = null;
    }

    public BuildPlan(Map<MavenProject, List<MavenProject>> projects) {
        this.projects = projects;
    }

    }

    static <K, V> Map<K, V> copy(Map<K, V> map) {
        if (map == null) {
            return emptyMap();
        } else if (map instanceof AbstractImmutableMap) {
            return map;
        } else {
            switch (map.size()) {
                case 0:
                    return emptyMap();
                case 1:
                    Map.Entry<K, V> entry = map.entrySet().iterator().next();

            });
    }

    private static <T> Map<AccessorKey, T> diff(Map<AccessorKey, T> first, Map<AccessorKey, T> second) {
        return first.entrySet().stream()
            .filter(e -> !second.containsKey(e.getKey()))
            .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
    }

import java.lang.annotation.RetentionPolicy;
import java.util.Map;
import java.util.Set;

/**
 * Optional features of classes derived from {@code Map}.
 *
 * @author George van den Driessche
 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible
public enum MapFeature implements Feature<Map> {
  /**

        Map<String, String> phases = new LinkedHashMap<>();
        for (Map.Entry<String, LifecyclePhase> e : lphases.entrySet()) {
            phases.put(e.getKey(), e.getValue().toString());
        }
        return phases;
    }

    @Deprecated
    public void setPhases(Map<String, String> phases) {
        Map<String, LifecyclePhase> lphases = new LinkedHashMap<>();
        for (Map.Entry<String, String> e : phases.entrySet()) {

		name   string
		input  map[string]interface{}
		expect clause.Values
	}{
		{
			name: "Test convert string value",
			input: map[string]interface{}{
				"name": "my name",
			},
			expect: clause.Values{
				Columns: []clause.Column{{Name: "name"}},
				Values:  [][]interface{}{{"my name"}},
			},
		},
		{
			name: "Test convert int value",
			input: map[string]interface{}{
				"age": 18,
			},

		keys           []string
		expectedFields map[string]struct{}
	}{
		// No keys present
		{
			input:          "",
			keys:           []string{"comment"},
			expectedFields: map[string]struct{}{},
		},
		// No keys requested for tokenizing
		{
			input:          `comment="Hi this is my comment ="`,
			keys:           []string{},
			expectedFields: map[string]struct{}{},
		},
		// Single key requested and present

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import static java.util.function.Function.identity;
import static java.util.stream.Collectors.toMap;

/**
 * DefaultLifecycleMapping
 */
public class DefaultLifecycleMapping implements LifecycleMapping {

    private List<Lifecycle> lifecycles;

    private Map<String, Lifecycle> lifecycleMap;

    /** @deprecated use lifecycles instead */

    }

    protected Optional<Map<String, String>> collectMapIfPresentOrEmpty(
            Function<O, Optional<Map<String, String>>> getter) {
        int had = 0;
        HashMap<String, String> items = new HashMap<>();
        for (O option : options) {
            Optional<Map<String, String>> up = getter.apply(option);
            if (up.isPresent()) {
                had++;

        list.add(newArtifact("c"));
        list.add(newArtifact("e"));
        list.add(newArtifact("d"));

        Map<String, Artifact> map = ArtifactUtils.artifactMapByVersionlessId(list);
        assertNotNull(map);
        assertEquals(list, new ArrayList<>(map.values()));
    }