<dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-api-metadata</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-api-model</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-api-toolchain</artifactId>
    </dependency>

    <dependency>

                dependency.getGroupId(),
                dependency.getArtifactId(),
                versionRange,
                dependency.getType(),
                dependency.getClassifier(),
                effectiveScope,
                dependency.isOptional());

        if (inheritedFilter != null && !inheritedFilter.include(dependencyArtifact)) {
            return null;

  <dependencies>

    <dependency>
      <groupId>maven-test-default</groupId>
      <artifactId>scope-default</artifactId>
      <version>1.0</version>
    </dependency>

    <dependency>
      <groupId>maven-test-default</groupId>
      <artifactId>scope-test</artifactId>
      <version>1.0</version>
      <scope>test</scope>
    </dependency>

    <dependency>
      <groupId>maven-test-default</groupId>

  <dependencies>

    <dependency>
      <groupId>maven-test-test</groupId>
      <artifactId>scope-default</artifactId>
      <version>1.0</version>
    </dependency>

    <dependency>
      <groupId>maven-test-test</groupId>
      <artifactId>scope-test</artifactId>
      <version>1.0</version>
      <scope>test</scope>
    </dependency>

    <dependency>
      <groupId>maven-test-test</groupId>

        // packaging type.
        for (Dependency dependency : dependencies) {
            String key = dependency.getGroupId() + ":" + dependency.getArtifactId() + ":" + dependency.getVersion()
                    + (dependency.getClassifier() != null ? ":" + dependency.getClassifier() : EMPTY);
            String mKey = m.getGroupId() + ":" + m.getArtifactId() + ":" + m.getVersion();

    }

    private Dependency convert(org.apache.maven.model.Dependency dependency, ArtifactTypeRegistry stereotypes) {
        ArtifactType stereotype = stereotypes.get(dependency.getType());
        if (stereotype == null) {
            stereotype = new DefaultType(dependency.getType(), Language.NONE, dependency.getType(), null, false);
        }

        boolean system = dependency.getSystemPath() != null

			<scope>provided</scope>
		</dependency>
		<dependency>
			<groupId>org.codelibs</groupId>
			<artifactId>sai</artifactId>
			<version>${sai.version}</version>
		</dependency>
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>${junit.version}</version>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.dbflute.utflute</groupId>

We can do better...

## What makes a dependency { #what-makes-a-dependency }

Up to now you have seen dependencies declared as functions.

But that's not the only way to declare dependencies (although it would probably be the more common).

The key factor is that a dependency should be a "callable".

A "**callable**" in Python is anything that Python can "call" like a function.

         * aftereffects and bogus error messages.
         */
        List<Dependency> dependencies = model.getDependencies();
        Map<String, Dependency> normalized = new LinkedHashMap<>(dependencies.size() * 2);

        for (Dependency dependency : dependencies) {
            normalized.put(dependency.getManagementKey(), dependency);
        }

        if (dependencies.size() != normalized.size()) {

        return plugin;
    }

    private Dependency createDependency(MavenProject project) {
        return createDependency(project.getGroupId(), project.getArtifactId(), project.getVersion());
    }

    private Dependency createDependency(String groupId, String artifactId, String version) {
        Dependency dependency = new Dependency();
        dependency.setGroupId(groupId);
        dependency.setArtifactId(artifactId);