Reader reader = request.getReader();
        InputStream inputStream = request.getInputStream();
        if (reader == null && inputStream == null) {
            throw new IllegalArgumentException("reader or inputStream must be non null");
        }
        try {
            InputSource source = null;
            if (request.getModelId() != null || request.getLocation() != null) {
                source = new InputSource(request.getLocation());

     * Normalizes the well-known URLs of the specified model.
     *
     * @param model The model whose URLs should be normalized, may be {@code null}.
     * @param request The model building request that holds further settings, must not be {@code null}.
     */
    Model normalize(Model model, ModelBuilderRequest request);

    /**
     * Tries to resolve the specified artifact from the artifacts of the given project.
     *
     * @param project The project to try to resolve the artifact from, must not be <code>null</code>.
     * @param requestedArtifact The artifact to resolve, must not be <code>null</code>.
     * @return The matching artifact from the project or <code>null</code> if not found. Note that this
     */

                        ModelProblem.Version.BASE,
                        "Invalid packaging for parent POM " + ModelProblemUtils.toSourceHint(parentModel)
                                + ", must be \"pom\" but is \"" + parentModel.getPackaging() + "\"",
                        parentModel.getLocation("packaging"));
            }
        }

        return parentData;
    }

/**
 * Builds up the transformer context.
 * After the buildplan is ready, the build()-method returns the immutable context useful during distribution.
 * This is an inner class, as it must be able to call readRawModel()
 *
 * @since 4.0.0
 */
class DefaultModelTransformerContextBuilder implements ModelTransformerContextBuilder {
    private final Graph dag = new Graph();

            Other values define only the prefix of classes/resources being exposed. Their binary name must be equal to the prefix or starting with the prefix (followed by "." or "$").

        InputStream inputStream = request.getInputStream();
        if (path == null && url == null && reader == null && inputStream == null) {
            throw new IllegalArgumentException("path, url, reader or inputStream must be non null");
        }
        try {
            PluginDescriptorStaxReader xml = new PluginDescriptorStaxReader();
            xml.setAddDefaultEntities(request.isAddDefaultEntities());

    @Test
    void testFileSource() {
        NullPointerException e = assertThrows(
                NullPointerException.class,
                () -> new FileSource((File) null),
                "Should fail, since you must specify a file");
        assertEquals("file cannot be null", e.getMessage());
    }

    @Test
    void testGetInputStream() throws Exception {
        File txtFile = new File("target/test-classes/source.txt");

          <version>4.0.0+</version>
          <description>
            <![CDATA[
            Just like {@code connection}, but for developers, i.e. this scm connection
            will not be read only.
            <p><b>Default value is</b>: parent value [+ path adjustment] + (artifactId or project.directory property), or just parent value if
            scm's {@code child.scm.developerConnection.inherit.append.path="false"}.</p>

        // ensure canonical order of standard lifecycles
        return lifecyclesMap.values().stream()
                .peek(l -> Objects.requireNonNull(l.getId(), "A lifecycle must have an id."))
                .sorted(Comparator.comparing(Lifecycle::getId, comparator))
                .collect(Collectors.toList());
    }

    private Map<String, Lifecycle> lookupLifecycles() {