return getProperties().elements();
    }

    @Override
    public Set<java.util.Map.Entry<Object, Object>> entrySet() {
        return getProperties().entrySet();
    }

    @Override
    public boolean equals(final Object o) {
        return getProperties().equals(o);
    }

    @Override
    public Object get(final Object key) {
        return getProperties().get(key);
    }

            initialProps.setProperty("shared.key", "initial.value");
            model.setProperties(initialProps);

            // Get two WrapperProperties instances from the same Model
            Properties wrapper1 = model.getProperties();
            Properties wrapper2 = model.getProperties();

            // Both wrappers should read the same initial value

            if (sourceDominant) {
                merged.putAll(target.getProperties());
                putAll(merged, source.getProperties(), CHILD_DIRECTORY_PROPERTY);
            } else {
                putAll(merged, source.getProperties(), CHILD_DIRECTORY_PROPERTY);
                merged.putAll(target.getProperties());
            }
            target.setProperties(merged);
            target.setLocation(

        props.putAll(getSystemProperties());
    }

    /**
     * Returns a copy of {@link System#getProperties()} in a thread-safe manner.
     *
     * @return {@link System#getProperties()} obtained in a thread-safe manner.
     */
    public static Properties getSystemProperties() {
        return copyProperties(System.getProperties());
    }

    /**

    }

    @Override
    public Artifact setProperties(Map<String, String> properties) {
        Map<String, String> current = getProperties();
        if (current.equals(properties) || (properties == null && current.isEmpty())) {
            return this;
        }
        return new RelocatedArtifact(
                artifact.setProperties(properties), groupId, artifactId, classifier, extension, version, message);

        Activation defaultActivation = new Activation();

        defaultActivation.setActiveByDefault(true);

        defaultActivated.setActivation(defaultActivation);

        Properties props = System.getProperties();

        ProfileManager profileManager = new DefaultProfileManager(getContainer(), props);

        profileManager.addProfile(notActivated);
        profileManager.addProfile(defaultActivated);

        model.addProperty("key1", "value1");
        model.addProperty("key2", "value2");
        assertEquals(2, model.getProperties().size());

        // This should not throw NullPointerException
        model.getProperties().clear();
        assertEquals(0, model.getProperties().size());
    }

        assertNotNull(result);
        assertNotNull(result.getEffectiveModel());
        assertEquals("activated-1", result.getEffectiveModel().getProperties().get("profile.file"));
        assertNull(result.getEffectiveModel().getProperties().get("profile.miss"));
    }

            String requiredMavenVersion = (String) result.getProperties().get("prerequisites.maven");
            if (requiredMavenVersion != null) {
                Map<String, String> props = new LinkedHashMap<>(pluginArtifact.getProperties());
                props.put("requiredMavenVersion", requiredMavenVersion);
                pluginArtifact = pluginArtifact.setProperties(props);
            }

        assertEquals("true", depArtifact.getProperty("constitutesBuildPath", null));
        assertEquals("false", depArtifact.getProperty("includesDependencies", null));
        assertEquals(4, depArtifact.getProperties().size());

        assertEquals("compile", dep2.getScope());
        assertFalse(dep2.isOptional(), "Expected " + dep2 + ".isOptional() to return false");
        assertEquals(0, dep2.getExclusions().size());