///

## Dependencies errors and return values { #dependencies-errors-and-return-values }

You can use the same dependency *functions* you use normally.

### Dependency requirements { #dependency-requirements }

They can declare request requirements (like headers) or other sub-dependencies:

{* ../../docs_src/dependencies/tutorial006_an_py39.py hl[8,13] *}

    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-api-settings</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-api-toolchain</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-api-plugin</artifactId>
    </dependency>
    <dependency>

    }

    private static String formatLocationInPom(Dependency dependency) {
        return "Dependency: " + ArtifactUtils.versionlessKey(dependency.getGroupId(), dependency.getArtifactId());
    }

    public Dependency getDependency() {
        return dependency;
    }

    public String getProjectId() {
        return projectId;
    }

    public File getPomFile() {
        return pomFile;
    }

This is quite simple (not very useful), but will help us focus on how the sub-dependencies work.

## Second dependency, "dependable" and "dependant" { #second-dependency-dependable-and-dependant }

Then you can create another dependency function (a "dependable") that at the same time declares a dependency of its own (so it is a "dependant" too):

{* ../../docs_src/dependencies/tutorial005_an_py310.py hl[13] *}

Let's focus on the parameters declared:

			<version>1.7.36</version>
		</dependency>
		<dependency>
			<groupId>org.slf4j</groupId>
			<artifactId>slf4j-reload4j</artifactId>
			<version>1.7.36</version>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.bouncycastle</groupId>
			<artifactId>bcprov-jdk18on</artifactId>
			<version>1.80</version>
		</dependency>
		<dependency>
			<groupId>org.junit.jupiter</groupId>

     *
     * @param dependency path to the dependency for which to get the module name
     * @return module name of the dependency at the given path, or empty if the dependency is not modular
     * @throws IOException if the module information of the specified dependency cannot be read
     */
    Optional<ModuleDescriptor> getModuleDescriptor(@Nonnull Path dependency) throws IOException;

    /**

import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.annotations.Nullable;
import org.apache.maven.api.annotations.Provider;

/**
 * Represents a dependency node within a Maven project's dependency collector.
 *
 * @since 4.0.0
 * @see org.apache.maven.api.services.DependencyResolverResult#getRoot()
 */
@Experimental
@Immutable
@Provider
public interface Node {

    /**

 * It's a node in the dependency graph and contains a {@code Dependency} instance. The {@code Dependency} instances are the outputs of the
 * collection process, part of the graph computed from one or more {@code DependencyCoordinates}.</p>
 *
 * <p>{@link org.apache.maven.api.DependencyScope} defines when/how a given dependency will be used by the

        return builder()
                .session(requireNonNull(session, "session cannot be null"))
                .groupId(requireNonNull(dependency, "dependency").getGroupId())
                .artifactId(dependency.getArtifactId())
                .version(dependency.getVersion().toString())
                .classifier(dependency.getClassifier())

    <dependencies>
      <dependency>
        <groupId>com.google.guava</groupId>
        <artifactId>guava</artifactId>
        <version>${project.version}</version>
      </dependency>
      <dependency>
        <groupId>com.google.guava</groupId>
        <artifactId>guava-gwt</artifactId>
        <version>${project.version}</version>
      </dependency>
      <dependency>
        <groupId>com.google.guava</groupId>